receptor tyrosine-protein kinase erbb-2

by: Bundit Boonyar i t 5410210278 Dept.Chemistry, Fac.Sc ience, Pr ince of Songkla Univers i ty

373-595 SP 3D Protein Structure

kinase erbB-2eceptor tyrosine-proteinR

by: Bundit Boonyar i t373-595 SP 3D Protein Structure 2

Protein: Receptor tyrosine-protein kinase erbB-2 Gene: Erbb2 (avian erythroblastosis oncogene B) Organism: Rattus norvegicus (Rat) Method: X-ray Diffraction (2.40 Å) Fragment: Extracellular region (residues 26-633)

PDB: 1N8Y


Entry Entry name Protein names Gene names Organism Length

UniProtKB Results

2 result(s) selected. (Clear selection)

P04412 EGFR_DROME Epidermal

growth factor

receptor

Egfr, cerbB, DER,top, CG10079

Drosophilamelanogaster(Fruit fly)

1,426

P06494 ERBB2_RAT Receptor

tyrosine

protein

kinase er...

Erbb2, Neu Rattusnorvegicus(Rat)

1,257

P21860 ERBB3_HUMAN Receptor

tyrosine

protein

kinase er...

ERBB3, HER3 Homosapiens(Human)

1,342


tyrosine

protein

kinase er...

ERBB2, HER2,MLN19, NEU, NGL

Homosapiens(Human)

1,255

Q61527 ERBB4_MOUSE Receptor

tyrosine

protein

kinase er...

Erbb4, Mer4 Musmusculus(Mouse)

1,308

Q62956 ERBB4_RAT Receptor

tyrosine

protein

kinase er...

Erbb4, Tyro2 Rattusnorvegicus(Rat)

1,308

Q15303 ERBB4_HUMAN Receptor

tyrosine

protein

kinase er...


1,308

P00533 EGFR_HUMAN Epidermal

growth factor

receptor

EGFR, ERBB,ERBB1, HER1

Homosapiens(Human)

1,210


tyrosine

protein

kinase er...

Erbb3 Musmusculus(Mouse)

1,339

P70424 ERBB2_MOUSE Receptor

tyrosine

protein

kinase er...

Erbb2, Kiaa3023,Neu

Musmusculus(Mouse)

1,256


tyrosine

protein

kinase er...

Erbb3 Rattusnorvegicus(Rat)

1,339

Q60553 ERBB2_MESAU Receptor

tyrosine

protein

kinase er...

ERBB2, NEU Mesocricetusauratus(Goldenhamster)

1,254

Q5RB22 ERBB3_PONAB Receptor

tyrosine

protein

kinase er...

ERBB3 Pongo abelii(Sumatranorangutan)(Pongo

1,342

Entry Entry name Protein names Gene names Organism Length

UniProtKB Results

2 result(s) selected. (Clear selection)

P04412 EGFR_DROME Epidermal

growth factor

receptor

Egfr, cerbB, DER,top, CG10079

Drosophilamelanogaster(Fruit fly)

1,426

P06494 ERBB2_RAT Receptor

tyrosine

protein

kinase er...

Erbb2, Neu Rattusnorvegicus(Rat)

1,257


tyrosine

protein

kinase er...


1,342


tyrosine

protein

kinase er...

ERBB2, HER2,MLN19, NEU, NGL

Homosapiens(Human)

1,255


tyrosine

protein

kinase er...

Erbb4, Mer4 Musmusculus(Mouse)

1,308


tyrosine

protein

kinase er...

Erbb4, Tyro2 Rattusnorvegicus(Rat)

1,308

Q15303 ERBB4_HUMAN Receptor

tyrosine

protein

kinase er...


1,308

P00533 EGFR_HUMAN Epidermal

growth factor

receptor

EGFR, ERBB,ERBB1, HER1

Homosapiens(Human)

1,210


tyrosine

protein

kinase er...

Erbb3 Musmusculus(Mouse)

1,339

P70424 ERBB2_MOUSE Receptor

tyrosine

protein

kinase er...

Erbb2, Kiaa3023,Neu

Musmusculus(Mouse)

1,256


tyrosine

protein

kinase er...

Erbb3 Rattusnorvegicus(Rat)

1,339

Q60553 ERBB2_MESAU Receptor

tyrosine

protein

kinase er...

ERBB2, NEU Mesocricetusauratus(Goldenhamster)

1,254

Q5RB22 ERBB3_PONAB Receptor

tyrosine

protein

kinase er...

ERBB3 Pongo abelii(Sumatranorangutan)(Pongo

1,342


What is receptor tyrosine-protein kinase erbB-2?


CHARACTERIZATION

140 Chapter 5: Growth Factors, Receptors, and Cancer

Since these initial analyses of the EGF receptor structure, a large number of other, sim-ilarly structured receptors have been characterized (Figure 5.9). As discussed later, each of these receptors has its own growth factor ligand or set of ligands (Table 5.1). Depending on the particular growth factor–receptor pair, the binding of a ligand to its

Figure 5.9 Structure of tyrosine kinase receptors The EGF receptor (Figure 5.8A) is only one of many similarly structured receptors that are encoded by the human genome. These tyrosine kinase receptors (RTKs) can be placed into distinct families, depending on the details of their structure. Representatives of most of these families are shown here. All have in common quite similar cytoplasmic tyrosine kinase domains (red), although in some cases (e.g., the PDGF receptor) these domains are interrupted by small “insert” regions. The RTK ectodomains (which protrude into the extracellular space, green, gray) have highly variable structures, reflecting the fact that they recognize and bind a wide variety of extracellular ligands. (From B. Alberts et al., Molecular Biology of the Cell, 5th ed. New York: Garland Science, 2008.)

EGFreceptor

SSSS

SS

insulinreceptor,

IGF-1receptor

NGFreceptor

PDGFreceptor,

M-CSFreceptor

FGFreceptor

plasma membraneCYTOPLASM

EXTRACELLULARSPACE

tyrosinekinasedomain

cysteine-richdomain

immunoglobulin-like domain

TBoC2 b5.10/5.09

VEGFreceptor

Ephreceptor

kinase insert region

fibronectin type III-like domain

Table 5.1 Growth factors (GFs) and tyrosine kinase receptors that are often involved in tumor pathogenesis

Name of GF Name of receptor Cells responding to GF

PDGFa PDGF-R endothelial, VSMCs, fibroblasts, other mesenchymal cells, glial cells

EGFb EGF-Rc many types of epithelial cells, some mesenchymal cells

NGF Trk neurons

FGFd FGF-Re endothelial, fibroblasts, other mesenchymal cells, VSMCs, neuroectodermal cells

HGF/SF Met various epithelial cells

VEGFf VEGF-Rg endothelial cells in capillaries, lymph ducts

IGFh IGF-R1 wide variety of cell types

GDNF Ret neuroectodermal cells

SCF Kit hematopoietic, mesenchymal cells

aPDGF is represented by four distinct polypeptides, PDGF-A, -B, -C, and -D. The PDGF-Rs consist of at least two distinct species, α and β, that can homodimerize or heterodimerize and associate with these ligands in different ways. bThe EGF family of ligands, all of which bind to the EGF-R (ErbB1) and/or heterodimers of erbB1 and one of its related receptors (footnote c), includes—in addition to EGF—TGF-α, HB-EGF, amphiregulin, betacellulin, and epiregulin. In addition, other related ligands bind to heterodimers of ErbB2 and ErbB3 or ErbB4; these include epigen and a variety of proteins generated by alternatively spliced neuregulin (NRG) mRNAs, including heregulin (HRG), glial growth factor (GGF), and less well-studied factors such as sensory and motor neuron–derived factor (SMDF). cThe EGF-R family of receptors consists of four distinct proteins, ErbB1 (EGF-R), ErbB2 (HER2, Neu), ErbB3 (HER3), and ErbB4 (HER4). They often bind ligands as heterodimeric receptors, for example, ErbB1 + ErbB3, ErbB1 + ErbB2, or ErbB2 + ErbB4; ErbB3 is devoid of kinase activity and is phosphorylated by ErbB2 when the two form heterodimers. ErbB2 has no ligand of its own but does have strong tyrosine kinase activity. ErbB3 and ErbB4 bind neuregulins, a family of more than 15 ligands that are generated by alternative splicing. dFGFs constitute a large family of GFs. The prototypes are acidic FGF (aFGF) and basic FGF (bFGF); in addition there are other known members of this family. eThere are four well-characterized FGF-Rs.fThere are four known VEGFs. VEGF-A and -B are involved in angiogenesis, while VEGF-C and -D are involved predominantly in lymphangiogenesis.gThere are three known VEGF-Rs: VEGF-R1 (also known as Flt-1) and VEGF-R2 (also known as Flk-1/KDR), involved in angiogenesis; and VEGF-R3, involved in lymphangiogenesis. hThe two known IGFs, IGF-1 and IGF-2, both related in structure to insulin, stimulate cell growth (that is, increase in size) and survival; they also appear to be weakly mitogenic.

Abbreviation: VSMC, vascular smooth muscle cell. Adapted in part from B. Alberts et al., Molecular Biology of the Cell, 5th ed. New York: Garland Science, 2008.

“Receptor Tyrosine Kinase (RTK)

“Cell growth”Structure of tyrosine kinase receptor

The Biology of Cancer, 2ed

“Enzyme linked receptor”“Cell surface receptor”


Epidermal growth factor www.rcsb.org/pdb

NH2

CO2H

Cell membrane

Ligand binding region

Catalytic binding region

Simplified representation

FIGURE 4.18 Structure of tyrosine kinase receptors.

a protein substrate are phosphorylated. An enzyme that catalyses phosphorylation reactions is known as a kinase enzyme and so the protein is referred to as a tyrosine kinase receptor. ATP is required as a cofactor to provide the necessary phosphate group. Th e active site remains open for as long as the messenger molecule is bound to the receptor, and so several phosphorylation reactions can occur, resulting in an amplifi cation of the signal. A curiosity of this enzyme-catalysed reaction is that the substrate for the reaction is the receptor itself. Th is is explained more fully in section 4.8.3.

Th e kinase-linked receptors are activated by a large number of polypeptide hormones, growth factors, and cytokines. Loss of function of these receptors can lead to developmental defects or hormone resistance. Over-expression can result in malignant growth disorders.

4.8.2 Structure of tyrosine kinase receptors Th e basic structure of a tyrosine kinase receptor consists of a single extracellular region (the N -terminal chain) that includes the binding site for the chemical messenger, a single hydrophobic region that traverses the membrane as an α-helix of seven turns (just suffi cient to traverse the membrane), and a C -terminal chain on the inside of the cell membrane ( Fig. 4.18 ). Th e C -terminal region contains the catalytic binding site. Examples of tyrosine kinase receptors include the receptor for insulin, and receptors for various cytokines and growth factors .

4.8.3 Activation mechanism for tyrosine kinase receptors A specifi c example of a tyrosine kinase receptor is the receptor for a hormone called epidermal growth factor (EGF). EGF is a bivalent ligand which can bind to two receptors at the same time. Th is results in receptor dimer-

ization , as well as activation of enzymatic activity. Th e dimerization process is important because the active site on each half of the receptor dimer catalyses the phospho-rylation of accessible tyrosine residues on the other half ( Fig. 4.19 ). If dimerization did not occur, no phosphoryla-tion would take place. Note that these phosphorylations occur on the intracellular portion of the receptor protein chain. Th e relevance of these phosphorylation reactions will be explained in section 5.4.1. Th e important point to grasp at this stage is that an external chemical messenger has managed to convey its message to the interior of the cell without itself being altered or having to enter the cell.

Dimerization and auto-phosphorylation are com-mon themes for receptors in this family. However, some of the receptors in this family already exist as dimers or tetramers, and only require binding of the ligand. For example, the insulin receptor is a heterotetrameric complex ( Fig. 4.20 ).

4.8.4 Tyrosine kinase-linked receptors Some kinase receptors bind ligands and dimerize in a similar fashion to the ones described above, but do not have inherent catalytic activity in their C -terminal chain. However, once they have dimerized, they can bind and activate a tyrosine kinase enzyme from the cytoplasm. Th e growth hormone (GH) receptor is an example of this type of receptor and is classifi ed as a tyrosine kinase-linked receptor ( Fig. 4.21 ).

KEY POINTS

• Kinase-linked receptors are receptors which are directly linked to kinase enzymes. Messenger binding results in the opening of the kinase-active site, allowing a catalytic reac-tion to take place.

• Tyrosine kinase receptors have an extracellular binding site for a chemical messenger and an intracellular enzymatic

54 Chapter 4 Receptors: structure and function

Patrick97397.indb 54 11/28/2012 9:12:40 PM

Structure of tyrosine kinase receptorAn Introduction to Medicinal Chemistry, 5ed

CHARACTERIZATION


FUNCTION132 Chapter 5: Growth Factors, Receptors, and Cancer

These signaling processes are part of the larger problem of cell-to-cell communica-tion. Indeed, the evolution of the first multicellular animals (metazoa) 600 to 700 mil-lion years ago depended on the development of biochemical mechanisms that allow cells to receive and process signals arising from their neighbors within tissues. With-out effective intercellular communication, the behavior of individual cells could not be coordinated, and the formation of architecturally complex tissues and organisms was inconceivable. Obviously, such communication depended on the ability of some cells to emit signals and of others to receive them and respond in specific ways.

In very large part, the signals passed between cells are carried by proteins. Hence, signal emission requires an ability by some cells to release proteins into the extracel-lular space. Such release—the process of protein secretion—is also complicated by the imperviousness of the plasma membrane. After these signaling proteins are released into the extracellular space, the designated recipient cells must be able to sense the presence of these proteins in their surroundings. Much of this chapter is focused on

LPAthrombin

ET, etc.TGF-α epiregulin amphi-

regulinNRG-1 cytokinesEGF β–cellulin HB-EGF NRG-2 NRG-3 NRG-4

SRC CBL PLC

PKC BAD S6K

AKT

PI3K SHP2 GRB7GRB2GAP

SHC

SOS

MAPK

RAF

RAC

MEK PAK ABL

JNK

NCK VAV CRK

STATERG1MYCSP1 FOS

JUN

ELK

JAKRAS-GDP

RAS-GTP

JNKK

growthfactorligands

cellsurfacereceptors

adaptorsandenzymes

signalingcascades

transcriptionfactors

INPU

T LAY

ER

APOPTOSIS MIGRATION GROWTH ADHESION DIFFERENTIATION

SIGN

AL PRO

CESSING

OU

TPUT

LAY

ER

= HER1 = HER2 = HER3 = HER4

TBoC2 b5.01/5.01

plasmamembrane

cytoplasm

nucleus

Figure 5.1 The human EGF receptor (HER) signaling network: how cells communicate with their surroundings A variety of protein messengers (growth factor ligands, light green rectangles, top) interact with a complex array of cell surface receptors, which transduce signals across the plasma membrane (gray) into the cytoplasm. There, a complex network of signal-transducing proteins processes these signals, funnels signals into the nucleus (bottom), and ultimately evokes a variety of biological responses (“output layer,” yellow rectangles, bottom). Many of the components of this circuitry, both at the cell surface and in

the cell interior, are involved in cancer pathogenesis. This cartoon focuses on a small subset of the receptors—the EGF receptor and its cousins—that are displayed on the surfaces of mammalian cells. Receptors like these are the main topic of this chapter; the adaptors and signaling cascades will be covered in the next chapter. The X’s associated with the cytoplasmic domain of HER3 indicate the absence of detectable tyrosine kinase activity in contrast to the readily detectable kinase activity of the other three members of this family of receptors. (From Y. Yarden and M.X. Sliwkowski, Nature Rev. Mol. Cell Biol. 2:127–137, 2001.)

The human EGF receptor (HER) signaling network: how cells communicate with their surroundingsThe Biology of Cancer, 2ed

Signal transduction


FUNCTION

Enzyme activationAn Introduction to Medicinal Chemistry, 5ed

than there are between the various subtypes of receptors which bind the same ligand. For example, the histamine H 1 receptor resembles a muscarinic receptor more closely than it does the histamine H 2 receptor. Again, this has important consequences in drug design because there is an increased possibility that a drug aimed at a muscarinic receptor may also interact with a histamine H 1 receptor and lead to unwanted side eff ects.

As these receptors are membrane bound, it is not easy to crystallize them for X-ray crystallographic studies. However, the X-ray crystal structures of the β 2 and β 1 adrenoceptors have now been determined.

4.7.4 Dimerization of G-coupled receptors Th ere is strong evidence that some G-coupled receptors can exist as dimeric structures containing identical or diff erent types of receptor—homodimers or heterodi-mers respectively. Th e presence of these receptor dimers appears to vary between diff erent tissues and this has important consequences for drug design. An agent that is selective for one type of receptor would not normally aff ect other types. However, if receptor heterodimers are present, a ‘communication’ is possible between the com-ponent receptors such that an agent interacting with one half of the dimer may aff ect the activity of the other half. Th is is discussed further in section 24.9 with respect to opioid receptors.

4.8 Kinase-linked receptors

4.8.1 General principles Kinase-linked receptors are a superfamily of receptors which activate enzymes directly and do not require a G-protein ( Fig. 4.17 ). Tyrosine kinase receptors are important examples of kinase-linked receptors and are proving to be highly important targets for novel anti-cancer drugs (section 21.6.2). In these structures, the protein concerned plays the dual role of receptor and enzyme. Th e receptor protein is embedded within the cell membrane, with part of its structure exposed on the outer surface of the cell and part exposed on the inner surface. Th e outer surface contains the binding site for the chemical messenger and the inner surface has an active site that is closed in the resting state. When a chemical messenger binds to the receptor it causes the protein to change shape. Th is results in the active site being opened up, allowing the protein to act as an enzyme within the cell. Th e reaction that is catalysed is a phosphorylation reaction where tyrosine residues on

KEY POINTS

• G-protein-coupled receptors activate signal proteins called G-proteins. Binding of a messenger results in the opening of a binding site for the signal protein. The latter binds and fragments, with one of the subunits departing to activate a membrane-bound enzyme.

• The G-protein-coupled receptors are membrane-bound proteins with seven transmembrane sections. The C -terminal chain lies within the cell and the N -terminal chain is extracellular.

• The location of the binding site differs between different G-protein-coupled receptors.

• The rhodopsin-like family of G-protein-coupled receptors includes many receptors that are targets for currently impor-tant drugs.

• Receptor types and subtypes recognize the same chemical messenger, but have structural differences, making it pos-sible to design drugs that are selective for one type (or sub-type) of receptor over another.

• Receptor subtypes can arise from divergent or convergent evolution.

• It is possible for some G-protein coupled receptors to exist as dimeric structures.

3

Cell

Cellmembrane

Cellmembrane

Messenger

AB

1

Cell Active site(closed)

2

Cell Active site(open)

Receptor Receptor Receptor

Messenger

Messenger

Cellmembrane

Cellmembrane

Cellmembrane

Cellmembrane

FIGURE 4.17 Enzyme activation.

Kinase-linked receptors 53

Patrick97397.indb 53 11/28/2012 9:12:39 PM

Second messenger

Effector

SignalingTarget cell


FUNCTION


A large extracellular portion

A section that crosses the cell membrane

A kinase domain

A long flexible tail (autophosphorylation)


FUNCTION


Symmetric

Asymmetric (head-to-tail)

Autophosphorylation

Dimerization


FUNCTION

involving JM-B, which we refer to as the ‘‘juxtamembrane latch,’’is crucial for receptor activation.

We show that JM-A segments on the receiver and the activatorare both required for dimerization and activation, and wepropose that the two JM-A segments in an asymmetric kinasedomain dimer form short a helices that are likely to interact inan antiparallel manner and connect to the C-terminal ends ofthe dimeric form of the transmembrane helices. This allowsa model for the entire activated receptor to be built, in whichligand engagement by the extracellular domains stabilizes theformation of the JM-A helical dimer, which in turn stabilizes theasymmetric kinase domain dimer, resulting in activation.

We have determined a structure of the EGFR kinase core inwhich formation of the juxtamembrane latch is blocked by theC-terminal tails of the receptor. This structure forms a symmet-rical dimer of inactive kinase domains and suggests a potentialmechanism whereby alternative dimers can prevent ligand-inde-pendent activation.

RESULTS

The Juxtamembrane Segment Activates the KinaseDomain in SolutionThe core kinase domain has low activity when measured in solu-tion with purified protein (the catalytic efficiency, kcat/KM, is0.0049 ± 0.0005 s!1mM!1, Figure 2A). Introduction of theL834R mutation, commonly found in lung cancer patients,increases the activity of the kinase core by "14-fold, consistentwith previous results (Yun et al., 2007; Zhang et al., 2006)(Figure 2A). Attachment of the juxtamembrane segment to thewild-type kinase domain results in substantially greater activity.The value of kcat/KM for the JM-kinase construct (0.33 ±0.02 s!1mM!1) is "70-fold greater than that for the kinase corealone. The activity of the kinase core is increased "20-fold byconcentrating it on lipid vesicles (Zhang et al., 2006), but the addi-tionof the juxtamembranesegment results in greater catalytic effi-ciency in solution, without concentration on vesicles (Figure 2A).

A

B

Figure 1. Schematic Diagrams of EGFR(A) Activation of EGFR by EGF results in the formation of an asymmetric kinase domain dimer.

(B) Domains of EGFR. Residue numbering corresponds to human EGFR, excluding the signal sequence.

1294 Cell 137, 1293–1307, June 26, 2009 ª2009 Elsevier Inc.

Jura et al. (2009)


FUNCTION

involving JM-B, which we refer to as the ‘‘juxtamembrane latch,’’is crucial for receptor activation.

We show that JM-A segments on the receiver and the activatorare both required for dimerization and activation, and wepropose that the two JM-A segments in an asymmetric kinasedomain dimer form short a helices that are likely to interact inan antiparallel manner and connect to the C-terminal ends ofthe dimeric form of the transmembrane helices. This allowsa model for the entire activated receptor to be built, in whichligand engagement by the extracellular domains stabilizes theformation of the JM-A helical dimer, which in turn stabilizes theasymmetric kinase domain dimer, resulting in activation.

We have determined a structure of the EGFR kinase core inwhich formation of the juxtamembrane latch is blocked by theC-terminal tails of the receptor. This structure forms a symmet-rical dimer of inactive kinase domains and suggests a potentialmechanism whereby alternative dimers can prevent ligand-inde-pendent activation.

RESULTS

The Juxtamembrane Segment Activates the KinaseDomain in SolutionThe core kinase domain has low activity when measured in solu-tion with purified protein (the catalytic efficiency, kcat/KM, is0.0049 ± 0.0005 s!1mM!1, Figure 2A). Introduction of theL834R mutation, commonly found in lung cancer patients,increases the activity of the kinase core by "14-fold, consistentwith previous results (Yun et al., 2007; Zhang et al., 2006)(Figure 2A). Attachment of the juxtamembrane segment to thewild-type kinase domain results in substantially greater activity.The value of kcat/KM for the JM-kinase construct (0.33 ±0.02 s!1mM!1) is "70-fold greater than that for the kinase corealone. The activity of the kinase core is increased "20-fold byconcentrating it on lipid vesicles (Zhang et al., 2006), but the addi-tionof the juxtamembranesegment results in greater catalytic effi-ciency in solution, without concentration on vesicles (Figure 2A).

A

B

Figure 1. Schematic Diagrams of EGFR(A) Activation of EGFR by EGF results in the formation of an asymmetric kinase domain dimer.

(B) Domains of EGFR. Residue numbering corresponds to human EGFR, excluding the signal sequence.

1294 Cell 137, 1293–1307, June 26, 2009 ª2009 Elsevier Inc.

Jura et al. (2009)

Phosphorylated tyrosines


FUNCTION

Jensen & Hunter (2001)

residues and tyrosine phosphorylation of substrates that are notphosphorylated by the activated wild-type Ret. However, there is also increased activation of PI(3)K, which might be crucial for transformation25.

A recently developed in vivomodel for MEN2B, based on introduc-tion of the Met918Thr homologous mutation into the germline ofmice, will enable studies of different signal-transduction pathwaysfrom Ret/MEN2B involved in tumorigenesis26. Besides the Met918Thrmutation, a number of other recurrent point mutations have beenfound in Ret in MEN2A, MEN2B and FMTC. In all cases, the activatingmutations occur in highly conserved regions of the Ret PTK domainthat are normally involved in kinase repression in the inactive receptor.Different tyrosine residues are likely to be autophosphorylated in thedifferent Ret mutants, resulting in binding and activation of differentsignalling molecules27. Based on mutagenesis studies, Grb2 and Shcacting upstream of the classical mitogenic Ras-Raf-ERK (for extracellular signal-regulated protein kinase) cascade and PI(3)K seem important for the transforming effects.

Kit/SCFRThe Kit/SCFR provided the first example of naturally occurring,germline loss-of-function (LOF) point mutations in a mammalianRPTK, and the resulting phenotypes established the importance of

this receptor for normal haematopoiesis and mast-cell development,melanogenesis, gametogenesis and development of interstitial cellsof Cajal28,29. Recently, more than 30 GOF mutations, either singleamino-acid changes or deletions of a few amino acids, have beenidentified in the Kit/SCFR, and they are associated with several highly malignant tumours in humans (reviewed in ref. 30). Themutations tend to cluster in two regions. Those in exon 11 containedin the juxtamembrane region are associated with gastrointestinalstromal tumours, whereas recurrent exon 17-mutations of Asp816 toeither Val or His in the second half of the kinase domain are associated with mast-cell/myeloid leukaemias and seminomas/dys-germinomas, respectively.

The transforming mechanism for both of the main types of mutation involves dimer formation resulting in constitutive ligand-independent kinase activation. In most patients, tumours are heterozygous for the mutant form of c-kit, which indicates a dominant-positive phenotype. This is consistent with constitutivelyactive heterodimers formed between the mutant and wild-type Kitreceptors. The mutations in the juxtamembrane region clusteraround the two autophosphorylation sites, Tyr568 and 570, involvedin binding c-Src and SHP-1 (an SH2 domain-containing protein-tyrosine phosphatase (PTP) expressed in haematopoietic cells)31,32,and the presence of mutant Kit implies a worse prognosis33. The

insight review articles

358 NATURE | VOL 411 | 17 MAY 2001 | www.nature.com

PP

PPN

C

Extracellular

Cytoplasm

a

N

C

ATP

PP

ATP

P P

PP

SH3SH3 SH3 ligands

SH2 ligandsSH2

SH2

PTK

Y416

PP

Activatingphosphorylation

Dephosphorylation

Y416

Y527

Cytoplasm

PTKP

P

P

Cytoplasm

b

c

NN

C C

P

P P

PH PHPH

PH Akt

Akt

PDK-1PDK-1T308T308

'Hydrophobic motifkinase' ('PDK-2')

S473

3'-Pls 3'-PlsPtdlns (4,5)P2

Y527

Figure 3 Protein kinase activation mechanisms. a, RPTK activation. Left: RPTK kinaseactivity is tightly repressed in the unstimulated state. The activation and catalytic loopsexist in an equilibrium between a substrate-precluding (blue) and substrate-accessible(green) conformation. In addition, the juxtamembrane region (orange) and C-terminalregion (red) might interfere with the conformation of the N-terminal kinase lobe (‘N’)and/or substrate access. Right: ligand-induced receptor dimerization and tyrosineautophosphorylation result in relief of the inhibitory constraints exerted by theactivation loop, and the juxtamembrane and C-terminal regions. b, c-Src activation.Left: c-Src kinase activity is tightly repressed in the unstimulated state. The SH2domain interacts with phospho-Tyr 527 in the C terminus and the SH3 domain withthe polyproline type II helix in the linker region between the SH2 and kinase domain.This causes misalignment of residues that are critical for kinase activity. Right: bindingof ligands to the SH2 or SH3 domain and/or dephosphorylation of phospho-Tyr 527 byPTPs relieves the inhibitory constraints on the kinase. c, Akt activation. Left: it isthought that the N-terminal PH domain precludes kinase access to andphosphorylation of the activation-loop Thr308 by PDK-1. Right: PI(3)K activationresults in production of PtdIns(3,4,5)P3 and PtdIns(3,4)P2, which recruits Akt to themembrane by binding to its PH domain. This exposes Thr308 for phosphorylation byPDK-1, which is already located at the membrane. An unidentified PDK-2 kinasephosphorylates Ser473 in the C terminus, which leads to full Akt activation. See textfor details.

© 2001 Macmillan Magazines Ltd








PP

PPN

C

Extracellular

Cytoplasm

a

N

C

ATP

PP

ATP

P P

PP

SH3SH3 SH3 ligands

SH2 ligandsSH2

SH2

PTK

Y416

PP


Dephosphorylation

Y416

Y527

Cytoplasm

PTKP

P

P

Cytoplasm

b

c

NN

C C

P

P P

PH PHPH

PH Akt

Akt

PDK-1PDK-1T308T308


S473


Y527










PP

PPN

C

Extracellular

Cytoplasm

a

N

C

ATP

PP

ATP

P P

PP

SH3SH3 SH3 ligands

SH2 ligandsSH2

SH2

PTK

Y416

PP


Dephosphorylation

Y416

Y527

Cytoplasm

PTKP

P

P

Cytoplasm

b

c

NN

C C

P

P P

PH PHPH

PH Akt

Akt

PDK-1PDK-1T308T308


S473


Y527










PP

PPN

C

Extracellular

Cytoplasm

a

N

C

ATP

PP

ATP

P P

PP

SH3SH3 SH3 ligands

SH2 ligandsSH2

SH2

PTK

Y416

PP


Dephosphorylation

Y416

Y527

Cytoplasm

PTKP

P

P

Cytoplasm

b

c

NN

C C

P

P P

PH PHPH

PH Akt

Akt

PDK-1PDK-1T308T308


S473


Y527



1. Inactive receptor monomer 2. Trans-autophosphorylation 3. Active phosphorylated receptor dimer


FUNCTION

© 2004 Nature Publishing Group44 | JANUARY 2005 | VOLUME 5 www.nature.com/reviews/immunol

R E V I EW S

immune system describe data obtained using lympho-cytes. Finally, we suggest that new discoveries showingthat even subtle alterations in PTPs can cause humandisease indicate that PTPs could be valuable drug targetsfor the treatment of immunological diseases.

Lymphocyte representatives of the ‘PTPome’We refer to the entire set of PTP genes in a genome asthe PTPome. Contrary to the assumption of manyresearchers a decade ago (and of some still today) thatPTPs are non-specific, unregulated housekeepingenzymes, of which cells only require one or two, it turnsout that the human PTPome is larger than expected. Infact, in the human genome, there are more genes thatencode PTPs6 than PTKs21 — 107 versus 90. Althoughthese numbers include several catalytically inactiveenzymes (both PTPs and PTKs) and PTPs that alsodephosphorylate other phospho-amino acids (that is,serine and/or threonine) or non-protein substrates(such as inositol phospholipids or mRNAs), they concurwith the growing experimental evidence that PTPs tendto be very specific and to have non-redundant, uniquefunctions. It is also becoming apparent that PTPs have amore active role in cellular processes than originallyappreciated; rather than being the enzymes that simplyreverse what PTKs accomplish, PTPs often have anactive regulatory role. In addition, many PTKs, such asthe SRC-FAMILY and SYK (spleen tyrosine kinase)-familyPTKs found in T and B cells, are tightly controlled byPTPs (BOX 1).

Lymphocytes express a remarkably high proportionof the 107 PTP genes in the human genome; T cellsexpress at least 45 different PTPs (TABLE 1), and B cellsseem to express a similar set. We anticipate that, after all107 PTP genes have been examined for lymphocyteexpression, the number of PTPs expressed by either

activation and secretion of interleukin-2 (IL-2).Althoughall of these pharmacological experiments were non-specific and were fraught with pitfalls, they indicated thatPTPs have a crucial role in both the maintenance of aresting lymphocyte phenotype and the reversion of acti-vated lymphocytes to a resting state during the termina-tion of an immune response. (Before these papers, othershad used vanadate in biochemical studies: for example, tostimulate tyrosine phosphorylation of membrane frac-tions from T and B cells20; however, at that time, themechanism by which vanadate mediated this effect wasunknown).

In this review, we discuss the repertoire of PTPs thatis present in cells of the immune system, the structures,functions and common themes of these enzymes andthe most recent advances in our understanding of theirmany roles in the immune response. We mainly focuson the importance of these enzymes in lymphocytes, inpart because most of the publications about PTPs in the

SRC FAMILY

A group of structurally relatedcytoplasmic and/or membrane-associated enzymes that arenamed after the prototypicalmember, SRC. Inhaematopoietic cells, SRCkinases — such as LCK, FYNand LYN — are the first proteintyrosine kinases that areactivated after stimulationthrough the immunoreceptors.They phosphorylate ITAMs(immunoreceptor tyrosine-based activation motifs) that are present in the signal-transducing subunits of theimmunoreceptors, therebyproviding binding sites for SRChomology 2 (SH2)-domain-containing molecules, such asSYK (spleen tyrosine kinase).

PTP

ATPPhosphorylatedsubstrate

Substrate P

P

PTK

Figure 1 | The phosphorylation ‘equation’. Tyrosinephosphorylation is a key mechanism for signal transduction andfor the regulation of many physiological processes. Proteins arephosphorylated on tyrosine residues by protein tyrosine kinases(PTKs) and dephosphorylated by protein tyrosinephosphatases (PTPs).

Box 1 | Regulation of crucial immune-cell protein tyrosine kinases by phosphorylation

Protein tyrosine kinases (PTKs) of the SRC, SYK (spleen tyrosine kinase), TEC and CSK (carboxy (C)-terminal SRCkinase) families are crucial for antigen-receptor-induced lymphocyte activation. SRC-family PTKs — that is, LCK, FYNand YES in T cells, and LYN, FYN and BLK (B-lymphoid kinase) in B cells — phosphorylate antigen-receptor subunitsand are required for lymphocyte activation. The activity of all SRC-family PTKs is positively regulated byphosphorylation of a conserved tyrosine residue in the activation loop (the tyrosine residue at position 394 (Y394) inLCK) and negatively regulated by phosphorylation of a tyrosine residue in the C-terminus (Y505 in LCK). The former is thought to be a site of autophosphorylation, and its phosphorylation is required for activity. Normally, SRC-familyPTKs are only phosphorylated at very low levels at this site. The C-terminal tyrosine residue is phosphorylated by thePTK CSK and results in the adoption of a suppressed conformation, in which the phosphorylated tail binds to the SRChomology 2 (SH2) domain in the same kinase molecule, which stabilizes an interaction of the SH3 domain with a motifin a short linker between the SH2 domain and the kinase domain. This conformation is referred to as the ‘tail bite’ and isshown for LCK in FIG. 3.

The SYK-family kinases — SYK and ZAP70 (ζ-chain-associated protein kinase of 70 kDa) — function downstream ofthe SRC-family kinases to amplify the signal and are focal points for the assembly of signalling complexes. ZAP70 isactivated by LCK-mediated phosphorylation of Y493 in its activation loop, and it subsequently autophosphorylatesabout ten tyrosine residues, including Y292,Y315,Y319 and Y492. Although some of these sites attract SH2-domain-containing substrates,Y292 functions as a negative-regulatory site by attracting the E3 ubiquitin ligase CBL (Casitas B-lineage lymphoma), which results in degradation of the T-cell receptor and disengagement and dephosphorylation of ZAP70.

TEC family PTKs — ITK (interleukin-2-inducible T-cell kinase), TXK and BTK (Bruton’s tyrosine kinase) inlymphocytes — function downstream of SRC PTKs and are positively regulated by phosphorylation, whereas CSK isphosphorylated only on the serine residue at position 364.

Protein tyrosine kinase

Signal in Signal out

Protein tyrosine phosphatase

Mustelin et al. (2005)


FUNCTION

UniProtP06494 - ERBB2_RAT

Protein Receptor tyrosineprotein kinase erbB2

Gene Erbb2

Organism Rattus norvegicus (Rat)

Status Reviewed

Annotation score: 5 out of 5 Experimental evidence at protein level iFunction

Protein tyrosine kinase that is part of several cell surface receptor complexes, but that apparentlyneeds a coreceptor for ligand binding. Essential component of a neuregulinreceptor complex, althoughneuregulins do not interact with it alone. GP30 is a potential ligand for this receptor. Regulatesoutgrowth and stabilization of peripheral microtubules (MTs). Upon ERBB2 activation, the MEMO1RHOADIAPH1 signaling pathway elicits the phosphorylation and thus the inhibition of GSK3B at cellmembrane. This prevents the phosphorylation of APC and CLASP2, allowing its association with the cellmembrane. In turn, membranebound APC allows the localization of MACF1 to the cell membrane,which is required for microtubule capture and stabilization (By similarity).In the nucleus is involved in transcriptional regulation. Associates with the 5'TCAAATTC3' sequencein the PTGS2/COX2 promoter and activates its transcription. Implicated in transcriptional activation ofCDKN1A; the function involves STAT3 and SRC. Involved in the transcription of rRNA genes by RNA PolI and enhances protein synthesis and cell growth (By similarity).

Catalytic activity

ATP + a [protein]Ltyrosine = ADP + a [protein]Ltyrosine phosphate.

Sites

Featurekey

Position(s) Length DescriptionGraphicalview

Featureidentifier

Actions

Binding site 755 – 755 1 ATP

Active site 847 – 847 1 Proton acceptor

Regions

Feature key Position(s) Length DescriptionGraphicalview

Featureidentifier

Actions

Nucleotide binding 728 – 736 9 ATP

GO - Molecular function

ATP binding DNA bindingglycoprotein binding Hsp90 protein bindingprotein heterodimerization activity protein tyrosine kinase activityreceptor signaling protein tyrosine kinase activityRNA polymerase I core bindingtransmembrane receptor protein tyrosine kinase activityubiquitin protein ligase binding

GO - Biological process

central nervous system developmentestrus glial cell differentiationliver development mammary gland involutionnegative regulation of apoptotic processpeptidyltyrosine phosphorylationperipheral nervous system developmentpositive regulation of cell growth

By similarity

By similarity

PROSITEProRule annotation

PROSITEProRuleannotation



Source: UniProtKBKW Source: UniProtKBKW

Source: RGD Source: RGD


Source: InterPro

Source: UniProtKB

Source: UniProtKBEC

Source: RGD

Source: RGD



Source: RGD

Source: GOC

Source: RGD

Source: UniProtKB


STRUCTURE

Interaction

Subunit structureHomodimer. Heterodimer with EGFR, ERBB3 and ERBB4. Part of a complex with EGFR and eitherPIK3C2A or PIK3C2B. May interact with PIK3C2B when phosphorylated on Tyr1198. Interacts withPRKCABP and PLXNB1. Interacts (when phosphorylated on Tyr1250) with MEMO1. Interacts withMUC1. Interacts (when phosphorylated on Tyr1141) with GRB7 (via SH2 domain). Interacts (whenphosphorylated on Tyr1250) with ERBB2IP Interacts with SRC, KPNB1, RANBP2, EEA1, CRM1, CLTC,PTK6, RPA94, MYOC and ACTB (By similarity).

Protein-protein interaction databases

MINT MINT132326.

Structure

Secondary structure

Legend: Helix Turn Beta strand

Show more details

3D structure databases

Select the linkdestinations:

PDBeRCSB PDB

PDBj

Entry Method Resolution (Å) Chain Positions PDBsum

1IIJ NMR A 647681 [»]

1N8Y Xray 2.40 C 23631 [»]

2J1H model A/B 649681 [»]

ProteinModelPortal P06494.

SMR P06494. Positions 23631, 6471027.

ModBase Search...

MobiDB Search...

Miscellaneous databases

EvolutionaryTrace P06494.

Family & Domains

Domains and Repeats

Featurekey


Featureidentifier

Actions

Domain 722 – 989 268 Protein kinase AddBLAST

Region

Featurekey


Featureidentifier

Actions

Region 678 – 691 14 Nuclear localizationsignal

AddBLAST

Region 678 – 691 14 Required for interactionwith KPNB1 and EEA1

AddBLAST

Region 1197 – 1199 3 Interaction with PIK3C2B

By similarity

1 1257


By similarity

By similarity

By similarity


SUBCELLULAR LOCATION

view identifier

Topological domain 23 – 654 632 Extracellular AddBLAST

Transmembrane 655 – 677 23 Helical AddBLAST

Topological domain 678 – 1257 580 Cytoplasmic AddBLAST

GO - Cellular component

apical plasma membrane basal plasma membranebasolateral plasma membraneintegral component of membranelateral loop membrane raftmicrovillus nucleusperinuclear region of cytoplasm plasma membranepostsynaptic membrane

Complete GO annotation...

Keywords - Cellular component

Cell membrane, Cytoplasm, Membrane, Nucleus

Pathology & Biotech

Keywords - Disease

Protooncogene

PTM / Processing

Molecule processing


Featureidentifier

Actions

Signal peptide 1 – 22 22 AddBLAST

Chain 23 – 1257 1235 Receptor tyrosineprotein kinaseerbB2

PRO_0000016671 AddBLAST

Amino acid modifications


Featureidentifier

Actions

Disulfide bond 26 쀫 53

Glycosylation 68 – 68 1 Nlinked (GlcNAc...)












Sequence Analysis

Sequence Analysis

Sequence Analysis


Source: RGD

Source: UniProtKBKW



Source: RGD Source: Reactome

Source: RGD

SequenceAnalysis

By similarity

Sequence Analysis

By similarity

Sequence Analysis

By similarity

By similarity

By similarity

By similarity

By similarity

By similarity

By similarity

1 Publication

By similarity

positive regulation of cell proliferation

positive regulation of MAPK cascade

positive regulation of phosphatidylinositol 3kinase signaling

positive regulation of Ras protein signal transduction

positive regulation of transcription from RNA polymerase III promoter

positive regulation of transcription from RNA polymerase I promoter

positive regulation of translation

protein autophosphorylation regulation of cell differentiation

regulation of cell proliferation

regulation of ERK1 and ERK2 cascade

regulation of microtubulebased process

response to axon injury response to drug

response to progesterone

skeletal muscle tissue development

sympathetic nervous system development

tongue development

transcription, DNAtemplated

transmembrane receptor protein tyrosine kinase signaling pathway


Keywords - Molecular function

Activator, Kinase, Receptor, Transferase, Tyrosineprotein kinase

Keywords - Biological process

Transcription, Transcription regulation

Keywords - Ligand

ATPbinding, DNAbinding, Nucleotidebinding

Enzyme and pathway databases

BRENDA 2.7.10.1. 5301.

Names & Taxonomy

Protein names Recommended name:Receptor tyrosineprotein kinase erbB2 (EC:2.7.10.1)

Alternative name(s):Epidermal growth factor receptorrelated protein

Protooncogene Neu

Protooncogene cErbB2

p185erbB2

p185neu

CD_antigen: CD340

Gene names Name:Erbb2Synonyms:Neu

Organism Rattus norvegicus (Rat)

Taxonomic

identifier

10116 [NCBI]

Taxonomic lineage Eukaryota › Metazoa › Chordata › Craniata › Vertebrata › Euteleostomi ›

Mammalia › Eutheria › Euarchontoglires › Glires › Rodentia › Sciurognathi ›

Muroidea › Muridae › Murinae › Rattus

Proteomes UP000002494: Unplaced

Organism-specific databases

RGD 2561. Erbb2.

Subcellular location

Cell membrane ; Singlepass type I membrane protein . Cytoplasm ›

perinuclear region . Nucleus

Topology

Feature key Position(s) Length DescriptionGraphical Feature

Actions

Source: RGD

Source: RGD

Source: RGD

Source: RGD

Source: UniProtKB

Source: UniProtKB

Source: UniProtKB


Source: RGD

Source: UniProtKB

Source: UniProtKB


Source: RGD

Source: RGD

Source: RGD

Source: RGD

Source: UniProtKBKW

Source: InterPro

By similarity By similarity

By similarity 1 Publication


FAMILY & DOMAIN

Interaction

Subunit structureHomodimer. Heterodimer with EGFR, ERBB3 and ERBB4. Part of a complex with EGFR and eitherPIK3C2A or PIK3C2B. May interact with PIK3C2B when phosphorylated on Tyr1198. Interacts withPRKCABP and PLXNB1. Interacts (when phosphorylated on Tyr1250) with MEMO1. Interacts withMUC1. Interacts (when phosphorylated on Tyr1141) with GRB7 (via SH2 domain). Interacts (whenphosphorylated on Tyr1250) with ERBB2IP Interacts with SRC, KPNB1, RANBP2, EEA1, CRM1, CLTC,PTK6, RPA94, MYOC and ACTB (By similarity).

Protein-protein interaction databases

MINT MINT132326.

Structure

Secondary structure

Legend: Helix Turn Beta strand

Show more details

3D structure databases

Select the linkdestinations:

PDBeRCSB PDB

PDBj

Entry Method Resolution (Å) Chain Positions PDBsum

1IIJ NMR A 647681 [»]

1N8Y Xray 2.40 C 23631 [»]

2J1H model A/B 649681 [»]

ProteinModelPortal P06494.

SMR P06494. Positions 23631, 6471027.

ModBase Search...

MobiDB Search...

Miscellaneous databases

EvolutionaryTrace P06494.

Family & Domains

Domains and Repeats

Featurekey


Featureidentifier

Actions

Domain 722 – 989 268 Protein kinase AddBLAST

Region

Featurekey


Featureidentifier

Actions

Region 678 – 691 14 Nuclear localizationsignal

AddBLAST

Region 678 – 691 14 Required for interactionwith KPNB1 and EEA1

AddBLAST

Region 1197 – 1199 3 Interaction with PIK3C2B

By similarity

1 1257


By similarity

By similarity

By similarity


MOLECULE PROCESSING

view identifier

Topological domain 23 – 654 632 Extracellular AddBLAST

Transmembrane 655 – 677 23 Helical AddBLAST

Topological domain 678 – 1257 580 Cytoplasmic AddBLAST

GO - Cellular component

apical plasma membrane basal plasma membranebasolateral plasma membraneintegral component of membranelateral loop membrane raftmicrovillus nucleusperinuclear region of cytoplasm plasma membranepostsynaptic membrane


Keywords - Cellular component

Cell membrane, Cytoplasm, Membrane, Nucleus

Pathology & Biotech

Keywords - Disease

Protooncogene

PTM / Processing

Molecule processing


Featureidentifier

Actions

Signal peptide 1 – 22 22 AddBLAST

Chain 23 – 1257 1235 Receptor tyrosineprotein kinaseerbB2

PRO_0000016671 AddBLAST

Amino acid modifications


Featureidentifier

Actions














Sequence Analysis

Sequence Analysis

Sequence Analysis


Source: RGD

Source: UniProtKBKW



Source: RGD Source: Reactome

Source: RGD

SequenceAnalysis

By similarity

Sequence Analysis

By similarity

Sequence Analysis

By similarity

By similarity

By similarity

By similarity

By similarity

By similarity

By similarity

1 Publication

By similarity


SEQUENCE ALIGNMENT

Align

AlignmentHow to print an alignment in color

***** ****:******** *.**************************************

P06494 ERBB2_RAT 1 MELAAWCRWGFLLALLPPGIAGTQVCTGTDMKLRLPASPETHLDMLRHLYQGCQVVQGNL 60

P04626 ERBB2_HUMAN 1 MELAALCRWGLLLALLPPGAASTQVCTGTDMKLRLPASPETHLDMLRHLYQGCQVVQGNL 60

****:*:****************:*******::*****************:********

P06494 ERBB2_RAT 61 ELTYVPANASLSFLQDIQEVQGYMLIAHNQVKRVPLQRLRIVRGTQLFEDKYALAVLDNR 120

P04626 ERBB2_HUMAN 61 ELTYLPTNASLSFLQDIQEVQGYVLIAHNQVRQVPLQRLRIVRGTQLFEDNYALAVLDNG 120

** :*.: . * :* ********************: ******** :****:*:*****

P06494 ERBB2_RAT 121 DPQDNVAASTPGRTPEGLRELQLRSLTEILKGGVLIRGNPQLCYQDMVLWKDVFRKNNQL 180

P04626 ERBB2_HUMAN 121 DPLNNTT-PVTGASPGGLRELQLRSLTEILKGGVLIQRNPQLCYQDTILWKDIFHKNNQL 179

* . ********* **:* ** .:***** **** ** *:*:.******* *********

P06494 ERBB2_RAT 181 APVDIDTNRSRACPPCAPACKDNHCWGESPEDCQILTGTICTSGCARCKGRLPTDCCHEQ 240

P04626 ERBB2_HUMAN 180 ALTLIDTNRSRACHPCSPMCKGSRCWGESSEDCQSLTRTVCAGGCARCKGPLPTDCCHEQ 239

******************************************* **************:*

P06494 ERBB2_RAT 241 CAAGCTGPKHSDCLACLHFNHSGICELHCPALVTYNTDTFESMHNPEGRYTFGASCVTTC 300

P04626 ERBB2_HUMAN 240 CAAGCTGPKHSDCLACLHFNHSGICELHCPALVTYNTDTFESMPNPEGRYTFGASCVTAC 299

*******:********* .********************************* .**:**

P06494 ERBB2_RAT 301 PYNYLSTEVGSCTLVCPPNNQEVTAEDGTQRCEKCSKPCARVCYGLGMEHLRGARAITSD 360

P04626 ERBB2_HUMAN 300 PYNYLSTDVGSCTLVCPLHNQEVTAEDGTQRCEKCSKPCARVCYGLGMEHLREVRAVTSA 359

*:*** ********************:* ***:**************************

P06494 ERBB2_RAT 361 NVQEFDGCKKIFGSLAFLPESFDGDPSSGIAPLRPEQLQVFETLEEITGYLYISAWPDSL 420

P04626 ERBB2_HUMAN 360 NIQEFAGCKKIFGSLAFLPESFDGDPASNTAPLQPEQLQVFETLEEITGYLYISAWPDSL 419

P06494 ERBB2_RAT 421 RDLSVFQNLRIIRGRILHDGAYSLTLQGLGIHSLGLRSLRELGSGLALIHRNAHLCFVHT 480

P04626 ERBB2_HUMAN 420 PDLSVFQNLQVIRGRILHNGAYSLTLQGLGISWLGLRSLRELGSGLALIHHNTHLCFVHT 479

P06494 ERBB2_RAT 481 VPWDQLFRNPHQALLHSGNRPEEDLCVSSGLVCNSLCAHGHCWGPGPTQCVNCSHFLRGQ 540

P04626 ERBB2_HUMAN 480 VPWDQLFRNPHQALLHTANRPE-DECVGEGLACHQLCARGHCWGPGPTQCVNCSQFLRGQ 538

P06494 ERBB2_RAT 541 ECVEECRVWKGLPREYVSDKRCLPCHPECQPQNSSETCFGSEADQCAACAHYKDSSSCVA 600

P04626 ERBB2_HUMAN 539 ECVEECRVLQGLPREYVNARHCLPCHPECQPQNGSVTCFGPEADQCVACAHYKDPPFCVA 598

P06494 ERBB2_RAT 601 RCPSGVKPDLSYMPIWKYPDEEGICQPCPINCTHSCVDLDERGCPAEQRASPVTFIIATV 660

P04626 ERBB2_HUMAN 599 RCPSGVKPDLSYMPIWKFPDEEGACQPCPINCTHSCVDLDDKGCPAEQRASPLTSIISAV 658

P06494 ERBB2_RAT 661 VGVLLFLILVVVVGILIKRRRQKIRKYTMRRLLQETELVEPLTPSGAMPNQAQMRILKET 720

P04626 ERBB2_HUMAN 659 VGILLVVVLGVVFGILIKRRQQKIRKYTMRRLLQETELVEPLTPSGAMPNQAQMRILKET 718

P06494 ERBB2_RAT 721 ELRKVKVLGSGAFGTVYKGIWIPDGENVKIPVAIKVLRENTSPKANKEILDEAYVMAGVG 780

P04626 ERBB2_HUMAN 719 ELRKVKVLGSGAFGTVYKGIWIPDGENVKIPVAIKVLRENTSPKANKEILDEAYVMAGVG 778

P06494 ERBB2_RAT 781 SPYVSRLLGICLTSTVQLVTQLMPYGCLLDHVREHRGRLGSQDLLNWCVQIAKGMSYLED 840

P04626 ERBB2_HUMAN 779 SPYVSRLLGICLTSTVQLVTQLMPYGCLLDHVRENRGRLGSQDLLNWCMQIAKGMSYLED 838

P06494 ERBB2_RAT 841 VRLVHRDLAARNVLVKSPNHVKITDFGLARLLDIDETEYHADGGKVPIKWMALESILRRR 900

P04626 ERBB2_HUMAN 839 VRLVHRDLAARNVLVKSPNHVKITDFGLARLLDIDETEYHADGGKVPIKWMALESILRRR 898

P06494 ERBB2_RAT 901 FTHQSDVWSYGVTVWELMTFGAKPYDGIPAREIPDLLEKGERLPQPPICTIDVYMIMVKC 960

P04626 ERBB2_HUMAN 899 FTHQSDVWSYGVTVWELMTFGAKPYDGIPAREIPDLLEKGERLPQPPICTIDVYMIMVKC 958

P06494 ERBB2_RAT 961 WMIDSECRPRFRELVSEFSRMARDPQRFVVIQNEDLGPSSPMDSTFYRSLLEDDDMGDLV 1020

P04626 ERBB2_HUMAN 959 WMIDSECRPRFRELVSEFSRMARDPQRFVVIQNEDLGPASPLDSTFYRSLLEDDDMGDLV 1018

P06494 ERBB2_RAT 1021 DAEEYLVPQQGFFSPDPTPGTGSTAHRRHRSSSTRSGGGELTLGLEPSEEGPPRSPLAPS 1080

P04626 ERBB2_HUMAN 1019 DAEEYLVPQQGFFCPDPAPGAGGMVHHRHRSSSTRSGGGDLTLGLEPSEEEAPRSPLAPS 1078

P06494 ERBB2_RAT 1081 EGAGSDVFDGDLAMGVTKGLQSLSPHDLSPLQRYSEDPTLPLPPETDGYVAPLACSPQPE 1140

P04626 ERBB2_HUMAN 1079 EGAGSDVFDGDLGMGAAKGLQSLPTHDPSPLQRYSEDPTVPLPSETDGYVAPLTCSPQPE 1138


SEQUENCE ALIGNMENT

Align
















********::*******:************ *****************:*:*******



****************:.**** * **..**.*..***:***************:*****



******** :*******. ::************.* **** *****.******* ***



*****************:***** ****************::**********:* **::*



**:**.::* **.*******:***************************************



************************************************************



**********************************.*************:***********














SEQUENCE ALIGNMENT

Align






























************************************************************



************************************************************



**************************************:**:******************



*************.***:**:*. .*:************:********** ********



************.**.:****** ** ***********:*** *********:******



You may add additional sequences to this alignment (in FASTAformat)

**** :*:**** ***** .*************************************.

P06494 ERBB2_RAT 1141 YVNQSEVQPQPPLTPEGPLPPVRPAGATLERPKTLSPGKNGVVKDVFAFGGAVENPEYLV 1200 P04626 ERBB2_HUMAN 1139 YVNQPDVRPQPPSPREGPLPAARPAGATLERPKTLSPGKNGVVKDVFAFGGAVENPEYLT 1198

*: *:* *** ***************: *:* ***.*:*****************

P06494 ERBB2_RAT 1201 PREGTASPPHPSPAFSPAFDNLYYWDQNSSEQGPPPSNFEGTPTAENPEYLGLDVPV 1257 P04626 ERBB2_HUMAN 1199 PQGGAAPQPHPPPAFSPAFDNLYYWDQDPPERGAPPSTFKGTPTAENPEYLGLDVPV 1255

Result InformationQuerysequences

>sp|P06494|ERBB2_RAT Receptor tyrosine-protein kinase erbB-2

OS=Rattus norvegicus GN=Erbb2 PE=1 SV=3

MELAAWCRWGFLLALLPPGIAGTQVCTGTDMKLRLPASPETHLDMLRHLYQGCQVVQGNL

ELTYVPANASLSFLQDIQEVQGYMLIAHNQVKRVPLQRLRIVRGTQLFEDKYALAVLDNR

DPQDNVAASTPGRTPEGLRELQLRSLTEILKGGVLIRGNPQLCYQDMVLWKDVFRKNNQL

APVDIDTNRSRACPPCAPACKDNHCWGESPEDCQILTGTICTSGCARCKGRLPTDCCHEQ

CAAGCTGPKHSDCLACLHFNHSGICELHCPALVTYNTDTFESMHNPEGRYTFGASCVTTC

PYNYLSTEVGSCTLVCPPNNQEVTAEDGTQRCEKCSKPCARVCYGLGMEHLRGARAITSD

NVQEFDGCKKIFGSLAFLPESFDGDPSSGIAPLRPEQLQVFETLEEITGYLYISAWPDSL

RDLSVFQNLRIIRGRILHDGAYSLTLQGLGIHSLGLRSLRELGSGLALIHRNAHLCFVHT

VPWDQLFRNPHQALLHSGNRPEEDLCVSSGLVCNSLCAHGHCWGPGPTQCVNCSHFLRGQ

ECVEECRVWKGLPREYVSDKRCLPCHPECQPQNSSETCFGSEADQCAACAHYKDSSSCVA

RCPSGVKPDLSYMPIWKYPDEEGICQPCPINCTHSCVDLDERGCPAEQRASPVTFIIATV

VGVLLFLILVVVVGILIKRRRQKIRKYTMRRLLQETELVEPLTPSGAMPNQAQMRILKET

ELRKVKVLGSGAFGTVYKGIWIPDGENVKIPVAIKVLRENTSPKANKEILDEAYVMAGVG

SPYVSRLLGICLTSTVQLVTQLMPYGCLLDHVREHRGRLGSQDLLNWCVQIAKGMSYLED

VRLVHRDLAARNVLVKSPNHVKITDFGLARLLDIDETEYHADGGKVPIKWMALESILRRR

FTHQSDVWSYGVTVWELMTFGAKPYDGIPAREIPDLLEKGERLPQPPICTIDVYMIMVKC

WMIDSECRPRFRELVSEFSRMARDPQRFVVIQNEDLGPSSPMDSTFYRSLLEDDDMGDLV

DAEEYLVPQQGFFSPDPTPGTGSTAHRRHRSSSTRSGGGELTLGLEPSEEGPPRSPLAPS

EGAGSDVFDGDLAMGVTKGLQSLSPHDLSPLQRYSEDPTLPLPPETDGYVAPLACSPQPE

YVNQSEVQPQPPLTPEGPLPPVRPAGATLERPKTLSPGKNGVVKDVFAFGGAVENPEYLV

PREGTASPPHPSPAFSPAFDNLYYWDQNSSEQGPPPSNFEGTPTAENPEYLGLDVPV

>sp|P04626|ERBB2_HUMAN Receptor tyrosine-protein kinase erbB-2

OS=Homo sapiens GN=ERBB2 PE=1 SV=1

MELAALCRWGLLLALLPPGAASTQVCTGTDMKLRLPASPETHLDMLRHLYQGCQVVQGNL

ELTYLPTNASLSFLQDIQEVQGYVLIAHNQVRQVPLQRLRIVRGTQLFEDNYALAVLDNG

DPLNNTTPVTGASPGGLRELQLRSLTEILKGGVLIQRNPQLCYQDTILWKDIFHKNNQLA

LTLIDTNRSRACHPCSPMCKGSRCWGESSEDCQSLTRTVCAGGCARCKGPLPTDCCHEQC

AAGCTGPKHSDCLACLHFNHSGICELHCPALVTYNTDTFESMPNPEGRYTFGASCVTACP

YNYLSTDVGSCTLVCPLHNQEVTAEDGTQRCEKCSKPCARVCYGLGMEHLREVRAVTSAN

IQEFAGCKKIFGSLAFLPESFDGDPASNTAPLQPEQLQVFETLEEITGYLYISAWPDSLP

DLSVFQNLQVIRGRILHNGAYSLTLQGLGISWLGLRSLRELGSGLALIHHNTHLCFVHTV

PWDQLFRNPHQALLHTANRPEDECVGEGLACHQLCARGHCWGPGPTQCVNCSQFLRGQEC

VEECRVLQGLPREYVNARHCLPCHPECQPQNGSVTCFGPEADQCVACAHYKDPPFCVARC

PSGVKPDLSYMPIWKFPDEEGACQPCPINCTHSCVDLDDKGCPAEQRASPLTSIISAVVG

ILLVVVLGVVFGILIKRRQQKIRKYTMRRLLQETELVEPLTPSGAMPNQAQMRILKETEL

RKVKVLGSGAFGTVYKGIWIPDGENVKIPVAIKVLRENTSPKANKEILDEAYVMAGVGSP

YVSRLLGICLTSTVQLVTQLMPYGCLLDHVRENRGRLGSQDLLNWCMQIAKGMSYLEDVR

LVHRDLAARNVLVKSPNHVKITDFGLARLLDIDETEYHADGGKVPIKWMALESILRRRFT


SEQUENCE ALIGNMENT

Align


***** ****:******** *.**************************************







































0

Align




****:*:****************:*******::*****************:********





































2

Align






** :*.: . * :* ********************: ******** :****:*:*****



































4

Align








* . ********* **:* ** .:***** **** ** *:*:.******* *********

































1

Align










******************************************* **************:*































0

Align












*******:********* .********************************* .**:**





























2

Align














*:*** ********************:* ***:**************************



























1


SEQUENCE ALIGNMENT

Align
















********::*******:************ *****************:*:*******

























2

Align


















****************:.**** * **..**.*..***:***************:*****























1

Align




















******** :*******. ::************.* **** *****.******* ***





















1

Align






















*****************:***** ****************::**********:* **::*



















4

Align
























**:**.::* **.*******:***************************************

















3

Align


























************************************************************















0

Align




























**********************************.*************:***********













0


SEQUENCE ALIGNMENT

Align






























************************************************************











0

Align
































************************************************************









0

Align


































**************************************:**:******************







0

Align




































*************.***:**:*. .*:************:********** ********





1

Align






































************.**.:****** ** ***********:*** *********:******


P04626 ERBB2_HUMAN 1079 EGAGSDVFDGDLGMGAAKGLQSLPTHDPSPLQRYSEDPTVPLPSETDGYVAPLTCSPQPE 1138 1


**** :*:**** ***** .*************************************.












































1



*: *:* *** ***************: *:* ***.*:*****************











































1


SEQUENCE ALIGNMENT

( ) + ( : ) + ( . ) = 150 amino acids

Conserved amino acids = 25 amino acids

( * ) = 1257 - 150 = 1107 amino acids

( * ) + Conserved amino acids = 1107 + 25 = 1132 amino acids

% identity = (1132/1257) x 100 = 90.06%


REFERENCES

[5] Weinberg, R. A. (2007). The Biology of Cancer: Garland Science.

[3] Mustelin, T., Vang, T., & Bottini, N. (2005). Protein tyrosine phosphatases and the immune response. Nat Rev Immunol, 5(1), 43-57.

[4] Patrick, G. L. (2013). An Introduction to Medicinal Chemistry: OUP Oxford.

[2] Jura, N., Endres, N. F., Engel, K., Deindl, S., Das, R., Lamers, M. H., . . . Kuriyan, J. Mechanism for Activation of the EGF Receptor Catalytic Domain by the Juxtamembrane Segment. Cell, 137(7), 1293-1307.

[1] Blume-Jensen, P., & Hunter, T. (2001). Oncogenic kinase signalling. Nature, 411(6835), 355-365.

T H A N K Y O U

receptor tyrosine-protein kinase erbb-2

Science

d protein structureby

d protein structurekinase

human receptorq62956

human receptorp04626

human receptorq61527

human receptorerbb4

neu rattusp06494 erbb2

receptor tyrosineproteinby