There's an interesting article published recently on this topic in TIG
[Trends in Genetics(1999): 15, 364 - Why have organelles retained
genomes?]. It's based on an hypothesis of John F. Allen that there's a
selective advantage for the proteins most susceptible to free radical
attack to be synthesized close to where damage is sustained frome these
radicals. Of course, for this to work, you have to keep all the synthetic
machinery to make these proteins. It makes sense to me, but perhaps
Saccone knew of some flaws in this argument that aren't apparent to me.
I'd be interested to hear if that was the case.
Andrew Gyles wrote:
> At a conference in Italy in 1994 Saccone et al said, 'The fundamental
> question..."why mtDNA and a separated organellar genetic system should
> have persisted throughout evolution?" is still waiting for a convincing
>> Has any progress been made in answering this question since then? The
> authors also said, 'Another intriguing question is why evolutionary
> process(es) led to the extant scenario: a genome with a reduced, but
> often similar information content in almost all organisms in spite of a
> great variation in size'.
>> To be more specific, I would ask why have the genes coding for
> respiratory enzymes remained in the mitochondrion in most cases instead
> of going to the nucleus?
>> 1. Progress in Cell Research, vol. 5, 131-135, (1995), Proceedings of
> the 23rd Bari Meeting on Bioenergetics.
>> Andrew Gyles
>> Sent via Deja.com http://www.deja.com/> Before you buy.
Australian Flora and Fauna Research Centre
Wollongong NSW 2522
Email: mdowton at uow.edu.au
Dept Applied and Molecular Ecology
Waite Campus, Adelaide University
Glen Osmond SA 5064