The Upright Ape: A New Origin of the Species
by Aaron G. Filler, MD, PhD
Figure 6-3 Cation Alterations of DNA/RNA Polymerases may Explain the Cambrian Explosion
Figure 6-3 Modification of Mutability by Environmental Factors
The rapidly evolving HIV genome demonstrates environmental effects on rate of mutation.
A The speed of reverse transcription from RNA to DNA is affected by the concentration of various elements in the medium.
B The polymerase enzyme produces fragments of the genome with standardized breakpoints sorted out by length in electrophoretic gel. Some elements cause improved readthrough longer segments of DNA so that certain bands disappear in some channels.
C RNA has a 3D structure of hairpins and loops. Breakpoints correspond to geometric twists and turns of the RNA.
D HIV genome shows high rates of transcript breakage at loops and bends.
|Figure credits -
A - From: Filler, A.G. and A. M. L. Lever (1996). Nucleic acid amplification using scandium and lanthanum ions. US Patent 5,554,498. and - Filler, A. G. and A. M. Lever (1997). Effects of cation substitutions on reverse transcriptase and on human immunodeficiency virus production. AIDS Research and Human Retroviruses 13(4): 291-9.
B - From: Filler, A. G. and A. M. L. Lever (2007). Molecular evidence for environmental trigger of mass evolutionary acceleration: an experimental model for the Cambrian Explosion. American Association for the Advancement of Science, Pacific Division. Boise, Idaho.
C - From: Alberts, B. (2002). Molecular Biology of the Cell. New York, Garland Science. Drawing reproduced by permission Garland Science, Taylor & Francis.
D - Redrawn, modified, after: Harrison, G. P., M. S. Mayo, E. Hunter, A.M.L. Lever. (1998). Pausing of reverse transcriptase on retroviral RNA templates is influenced by secondary structures both 5' and 3' of the catalytic site. Nucleic Acids Research 26(14): 3433-42.