Re: Spliceosomal introns


"Perplexed in Peoria" <jimmenegay@xxxxxxxxxxxxx> wrote in message news:dtd3aj$21ss$1@xxxxxxxxxxxxxxxxxxxxxx

Here is another recent review article on eukaryote introns. Available
free online, but may require registration.

http://www.nature.com/hdy/journal/v96/n3/abs/6800791a.html

Review
Heredity (2006) 96, 208?213.
The rise and falls of introns
R Belshaw and D Bensasson

Abstract
There has been a lively debate over the evolution of eukaryote
introns: at what point in the tree of life did they appear and
from where, and what has been their subsequent pattern of loss
and gain? A diverse range of recent research papers is relevant
to this debate, and it is timely to bring them together. The
absence of introns that are not self-splicing in prokaryotes
and several other lines of evidence suggest an ancient eukaryotic
origin for these introns, and the subsequent gain and loss of
introns appears to be an ongoing process in many organisms.
Some introns are now functionally important and there have
been suggestions that invoke natural selection for the ancient
and recent gain of introns, but it is also possible that fixation
and loss of introns can occur in the absence of positive selection.


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