My evolution hypothesis

[LucidDreamer]

I believe that a major method of evolution occurs on allosteric regions of enzymes (which are the regions of the enzyme that are not involved in the chemical reaction).

 

Cells have extremely complex methods of regulation that provide a buffer zone in the amount of an enzyme that can exist within the cell. When mutations that create additional copies of a gene that codes for an enzyme occur, the organism can often function just fine with some extra enzyme present because of its regulation system. The enzyme is then given breathing room to mutate until it creates an additional active region that performs a different but useful function for the cell. In this case, if the additional amount enzyme is not needed the active region of the enzyme is free to mutate as well.

 

I suspect that many multiple copy genes provide the breeding grounds for the evolution of new enzymes that perform different catalytic functions on the allosteric sites. In the case of multiple copy genes where each copy of the gene is useful, yet the full efficiency of the resulting enzyme is not necessary for survival, I believe that some copies of the gene mutate until they are performing dual roles with two separate enzymatic functions with various degrees of efficiency in each role.

 

If my hypothesis is correct then you should be able to find several instances with multiple copy genes where one or more of the copies still perform the original function yet they also perform a separate and useful catalytic function. These dual-role enzymes should have much of their DNA involved in the structure of the original active site in common with the other copies yet have differences in the allosteric regions of the gene. You should also find many instances of genes in the organism's genome with various degrees of change towards a separate enzyme.

 

I wouldn't be surprised if this has already been thoroughly studied and I am merely presenting a hypothesis with a process that as already been well-documented. Does anyone have any thoughts or relevant information about my hypothesis?

[Mokele]

I dunno about the dual-function enzyme, but the process by which gene duplications allow the copy to mutate into a new function is well know. Indeed, many genes are studies as part of "gene families", with an excellent example of this being hemoglobin and myoglobin genes.

 

Mokele

[LucidDreamer]

Yeah, I knew about the gene duplication. I was wondering about the dual-function enzymes, the allosteric mutation, and multi-gene part. I was wondering how influential that model has been in evolution.

[Mokele]

I've got no idea there. Molecular really isn't my thing, and I don't keep up to date with it.

 

Mokele