Saturday, December 14, 2013

Science - Exonic Transcription Factor Binding

M. Madan Babu, PhD
MRC Laboratory of Molecular Biology, Cambridge, UK
image Madan homepage

Science reports:

The Hidden Codes That Shape Protein Evolution

Despite redundancy in the genetic code, the choice of codons used is highly biased in some proteins, suggesting that additional constraints operate in certain protein-coding regions of the genome. This suggests that the preference for particular codons, and therefore amino acids in specific regions of the protein, is often determined by factors unrelated to protein structure or function. On page 1367 in this issue, Stergachis et al. reveal that transcription factors bind within protein-coding regions (in addition to nearby noncoding regions) in a large number of human genes. Thus, a transcription factor “binding code” may influence codon choice and, consequently, protein evolution. This “binding” code joins other “regulatory” codes that govern chromatin organization, enhancers, mRNA structure, mRNA splicing, microRNA target sites, translational efficiency, and cotranslational folding, all of which have been proposed to constrain codon choice, and thus protein evolution.

See also Nature World News:  DNA has Secret Code for Gene Control, Scientists say

Now this is what I call significant news on the study of DNA and evolution. Not only amino acid sequences and replicating proteins but a second, previously hidden coding mechanism, that guides the DNA an shows what an incredibly efficient storage system of information it is.

Sooner or later someone will seriously start to ask where the information written in such wondrously powerful ways into the DNA comes in the first place.

Sooner or later.