The Evolution of Circular RNA: A Marshall McLuhan Moment

Semi OT: Watching a protein as it functions - March 15, 2013 Excerpt: When it comes to understanding how proteins perform their amazing cellular feats, it is often the case that the more one knows the less one realizes they know. For decades, biochemists and biophysicists have worked to reveal the relationship between protein structural complexity and function, only to discover more complexity. One challenging aspect of protein behavior has been the speed with which they change shape and interact with their neighboring biomolecules. Until recently, researchers have relied on a somewhat static approach, using freeze-trapping to capture protein intermediates at various steps along a biochemical pathway. But exciting breakthroughs now allow us to watch proteins changing in real time.,,, A signaling protein usually responds to a messenger or trigger, such as heat or light, by changing its shape, which initiates a regulatory response in the cell. Signaling proteins are all-important to the proper functioning of biological systems, yet the rapid sequence of events, occurring in picoseconds, had, until now, meant that only an approximate idea of what was actually occurring could be obtained.,, The team identified four major intermediates in the photoisomerization cycle. ,,, By tracking structurally the PYP photocycle with near-atomic resolution, the team provided a foundation for understanding the general process of signal transduction in proteins at nearly the lightning speed in which they are actually happening. http://phys.org/news/2013-03-protein-functions.htmlbornagain77

March 15, 2013

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C.H. I think you are conflating "evolution" with conjectured neo-Darwinian (ND) mechanism of such transformation, the random mutation. It is is the "random" (aimless, purposeless) assumption that is gratuitous. To see the difference, consider copyright lawsuits for the "evolution" between pieces of music, books, software,... In all such instances, the improbable degree of similarity/identity between, say, the two books, "Old" and "New" is a perfectly justifiably taken to imply "evolution" of Old into New book i.e. the copying of the Old by the author of New. Hence, there is nothing wrong with the inference of "evolution" (transformation) from "Old" into "New" based on high enough degree of similarity. That simply follows from much greater unlikelyhood of "New" just by chance producing the observed high degree of similarity with the Old. But in all cases of "evolution" where the explanation is known, the transformation Old -> New, as well as the creation of the original "Old" is product intelligent or anticipatory process. The problem with neo-Darwinian story is that they insist that biological evolution (as justifiably inferred from similarity) is somehow exception to the unbroken pattern observed elsewhere, that only in biology, contrary to all other explained instances of evolution, the evolution is produced by "random" mutation+natural selection. It is the "randomness" conjecture which is unjustified and which they should be defending instead of shifting the debate to defending the 'transformation'/'evolution' aspect (allowed by your terminological blurring), which they will always win since it is the most plausible explanation of the similarity. Hence, this blurring of "evolution" and "ND evolution" weakens greatlty otherwise good points you are making since on its face you appear to be denying what is in every other field completely obvious -- if some book New has pages and pages identical to some previous book Old it is perfectly natural to infer that New evolved from Old. What you need to argue is that RM+NS mechanism cannot account for either the creation of Old or for Old -> New transformation, but not that Old -> New transformation did not occur (since that is the most reasonable explanation of similarity between New and Old).nightlight

March 15, 2013

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