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I found the following research quite intriguing. It has far reaching implications of interest to IDists. One implication requires a front-loading IDist to appreciate. Basically what the researchers found is that there are risk assessments in the promoter regions of genes. If a gene is critical and random mutations to it would be bad news it is marked as high risk and isn’t subject to mutation. If it’s not so critical it is marked low risk and exposed to experimentation.
How does this apply to front-loading? A major problem for front-loading is no known mechanism for conservation of genomic information other than natural selection. Information stored for a distant future that isn’t used in the present is ostensibly destroyed by deep time and random mutation. Other research we’ve blogged here showed compelling evidence that a mechanism for conserving unexpressed information exists. This is even more compelling – tags saying “conserve this”. Now all we need to find is the enhanced error detection and correction mechanism that is employed to conserve information tagged for conservation and there’s our mechanism for presevation of front-loaded genomic information over deep time.
Evolution: When Are Genes ‘Adventurous’ And When Are They Conservative?
ScienceDaily (Nov. 8, 2007) — Taking a chance on an experiment – this is one of the impulses that drive evolution. Living cells are, from this angle, great subjects for experimentation: Changes in one molecule can have all sorts of interesting consequences for many other molecules in the cell. Such experiments on genes and proteins have led the cell, and indeed all life, on a long and fascinating evolutionary journey.
Prof. Naama Barkai of the Weizmann Institute’s Molecular Genetics Department recently took a look at gene expression – the process in which the encoded instructions are translated into proteins – and the evolution of mechanisms in the cell for controlling that expression. Changes in genes, and thus in protein structure, are a double-edged sword: They can give cells new abilities or advantages for survival, but they can also spell disease or death for the organism. Not all genes evolve at the same rate. Indeed, some have been conserved through long stretches of evolution: Similar versions of some genes are found in yeast, plants, worms, flies, and humans.
When do cells hold on to specific gene sequences, and when do they allow evolution to experiment with them? Clearly, highly conserved genes fulfill some basic, universal function for all life, and changes in their sequences have drastic consequences, involving death or the inability to multiply. How does evolution “decide” which genes need to be conserved, and which it can change freely? What keeps these genes safe from the ongoing experimentation that’s constantly carried out on other genes?
Barkai and her team discovered a sort of “risk distribution law” for evolution. They found that a genetic “phrase” that regularly shows up in the promoter region of genes (the bit of genetic code responsible for activating the gene) contains a key to gene conservation: The expression of a gene that contains the sequence TATA in its promoter is more likely to have evolved than that of a gene that does not have TATA in its promoter.
In other words, the level of risk appears to written in the gene code, in a way that’s similar to financial risk analysis: When the cost of error is high, an investor’s willingness to chance the risk is low, but if the cost of a mistake is negligible, even if the chance of making one is high, the possibility of gain may make the risk worthwhile. Evolution, it seems, discovered this principle millions of years before Wall Street.
Read the rest of the article at the source here