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Here is How Genes Are Exquisitely Timed

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You learned in your high school biology class that genes are copied, or transcribed, and that the transcript was used by the ribosome to synthesize a protein. But how does the cell know which genes to transcribe, which form of the gene to use, and when to transcribe it? These questions are answered by various mechanisms collectively referred to as gene regulation. The DNA region upstream of a gene may have various molecules and proteins attached which influence its expression, that DNA region and the histone proteins about which it is wrapped may have methyl groups or other small groups attached to them serving as signals, once transcribed the resulting mRNA transcript may be spliced into alternate forms, the mRNA transcript can also be controlled by snippets of RNA that bind to the transcript, the speed with which the transcript is translated into a protein can be controlled at the ribosome, and so forth. It is an incredible network of signals and mechanisms controlling which genes are used, how they are used, and when they are used. Now, new research is helping to elucidate yet another mechanism which is the equivalent of a fine-control knob on the timing of the transcription process.  Read more

Related note to 'exquisitely timed': A New Study Adds Further Depth to the Information Story - JonathanM - March 2012 Excerpt: The conventional genetic code involves 20 different amino acids, which map to 64 different triplets of nucleotides called codons. Since there are many more codons than amino acids, this means that there is an element of redundancy because amino acids can be specified by multiple codons. As I noted before, this redundancy allows the genetic code to be exquisitely fine-tuned to minimize error. The paper explains that "redundancy in the genetic code allows the same protein to be translated at different rates." In other words, even so-called silent substitutions (that is, those mutations that exchange a nucleotide for another without changing the amino acid specified by the codon) can have an impact on the rate of translation of the protein product. http://www.evolutionnews.org/2012/03/new_study_adds058051.html bornagain77
I need to thank Prof. Granville Sewell for pointing out the 'environment' vs 'organism' sleight of hand by neo-Darwinians. What are the odds of the whole system, such as Earth+Sun, arranging via pure random collisions into us typing here, on other random arrangements, keyboards, which are driving other random arrangements, computers, sending random electric pulses into Ethernet cables,... nightlight
Why is that a mystery? The molecules of some system X collided randomly into this arrangement, then some other nearby molecules E, environment, collided randomly on their own among themselves, then molecules of E collided randomly with molecules of X, "selecting" this configuration of X. And that's how it all came about, like ping-pong. No mystery at all :) nightlight

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