Time, seconds

1E-3 0.01 0.1 1 10 100

0.0

0.2

0.4

0.6

0.8

1.0

Nucleotides 95-97

0.0

0.2

0.4

0.6

0.8

1.0

Nucleotides 109-112

0.0

0.2

0.4

0.6

0.8

1.0

Nucleotide 122

Fractional Saturation

0.0

0.2

0.4

0.6

0.8

1.0

Nucleotides 139-141

Seconds Supplementary Material Figure 4: Left: Autoradiogram of the ·OH cleavage products of the Tetrahymena ribozyme upon its Mg2+-induced folding starting at 200 mM Na+ and folded in the presence of 600 mM Na+. Right: Changes in solvent accessibility of protected regions and the regions of enhanced reactivity were quantitated as described in Material and Methods. This figure is taken from Shcherbakova, I. Mitra, S., Beer, R. & Brenowitz, M. (2007) Following molecular transitions with single residue spatial and millisecond time resolution in Biophysical Tools for Biologists Volume 1, J.J. Correia and H.W. Detrich editors, Elsevier / Academic Press, volume in press.