You wrote…

Y'gotta get up pretty early in the morning to out rabbit me. Behold. But thanks anyway!

lol I should have guessed. Sorry I didn't notice/remember you had already posted it.

You wrote…

The gene that encodes the protein RecA should be designated recA (lowercase italics).

Thank you for the information.

I had assumed a segment of DNA was responsible for the protein but I wasn't sure. That is why I asked the question. Life is full of chicken and egg problems. I am not surprised to see that here too (and don't see it as a significant negative).

Again, thanks.

Y'gotta get up pretty early in the morning to out rabbit me. Behold. But thanks anyway!

Mike:

Finally, if RecA is an evolution gene, this would lead to an obvious prediction

TP:
However, just to make sure I understand correctly, RecA along with the Rad51 and RadA versions are proteins. Isn't this a looser definition of "gene" than strickly "a segment of DNA".

No, Mike appears to be using a narrow definition of gene (segment of DNA encoding a protein) combined with slightly sloppy editing. The gene that encodes the protein RecA should be designated recA (lowercase italics).

In other words, recombination occurs because tubulin-like proteins stretch the DNA by forming a dynamically lengthening tube around it. In this way, the growing protein tube can hold onto the single stranded DNA with one "hand" while using its other "hands" to unravel double stranded DNA such that the single-stranded DNA can be used to probe the unraveled DNA for regions that are complementary.

Given its DNA-linked function, its versatility and its universality RecA is a likely tool kit nominee.

A microtubule-like structure is thus in charge of genetic recombination. Finally, if RecA is an evolution gene, this would lead to an obvious prediction - removal of RecA should compromise an organism's ability to evolve. We'll consider this prediction in the next installment.

Good cliffhanger. It is difficult to conceive of life without RecA or at least a functional equivalent. What would a pre-RecA world have been like?

RecA has been long been known to be a requirement for bacterial evolution:

http://jb.asm.org/cgi/content/...

Other interesting papers on this are Barbara Wright's:

http://jb.asm.org/cgi/content/...
(there was another interesting one by her, but I can't find it at the moment)

Also see anything by Caporale, including this volume for which she is editor:

http://www.nyas.org/annals/det...

Have you seen this?

http://dfcord.blogspot.com/200...

I thought you might like this.

In the linked article from your web site you wrote…

A microtubule-like structure is thus in charge of genetic recombination.

Finally, if RecA is an evolution gene, this would lead to an obvious prediction - removal of RecA should compromise an organism's ability to evolve. We'll consider this prediction in the next installment.

Ok, you got my attention. I will be looking into this further.

However, just to make sure I understand correctly, RecA along with the Rad51 and RadA versions are proteins. Isn't this a looser definition of "gene" than strickly "a segment of DNA".

I don't ask this to be a trouble-maker, I ask it to check my comprehension.