Transposon

“Jumping Genes”DNA Sequence that moves from one location to another

Insertion Sequence

“retro” – made with transcriptase (like virsuses)

Transposon

Direct repeats

Composite

Adds extra genes between two insertions

Regulation of Metabolic Pathway

Regulate genes

Regulates enzymes

Operons

A unit of genetic material that functions in bacteria and phages

Clustered gene with one promoter

On/off switch

Negative Gene Regulation

Repressible operonsTranscription is inhibited

Inducible operonsTranscription is stimulated

The trp Operon

Corepressor – absent makes tryptophan

Repressor

Corepressor – present stops tryptophan productionCorepressor – helper for repressor

lac operon

Lactose absent / repressor active – operon off

lac operon

Lactose present / repressor inactive – operon oninducer

Positive Gene Regulation

cAMPAccumulates when glucose is scarce

Chromatin

Nucleosome

DNA and histone proteins together

Repetitive DNA

Gene Amplification

Not passed to childrenEmbryos – ribosome production

Cancer cells – drug resistance

Questions???

Gene loss??

Gene rearrangement??

Genome??

Gene Expression

Transcription Factors

A protein that binds to DNA and allows for RNA polymerase to attach and begin transcription

Enhancers – bends DNA to allow the factors to be closer to the promoter region

RNA Splicing

Allows alternative mRNA molecules to be built – ex. exons will act as introns

Recombinant DNA

Proteasome

A giant protein complex that destroys proteins tagged for elimination by ubiquitin.

DNA Testing

PCR

RFLP

Practical Application

Diagnosis of Diseases

Human Gene Therapy

DNA Fingerprinting

Environmental Uses

Agricultural Uses

Human Genome Project

Safety and Ethical Questions

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