Tom Matthews wrote:
> How many of the 13 mitochondrial mammalian genes have found their way
> into the nucleus of some plant?
I know of seven -- six in one genus, Chlamydomonas, and one each in a
few others. A very comprehensive recent reference on such things is
Leblanc et al, Curr Genet 1997; 31:193-207.
> Is there active work proceeding to attempt to mimick these gene
> transfers in some mammal? and if not why not? It seems to me this should
> be a top priority.
No, though I couldn't agree more. The main reason why not seems to be
that early (primitive) attempts, by people who weren't working on aging
anyway, gave unpromising results and they gave up too easily. I know of
only one lab currently working on pushing the boundaries of mitochondrial
import of hydrophobic proteins, and they're doing it in yeast. There are
absurdly many obvious, inexpensive experiments to be done.
> Is there any correlation between the longevity of plants and the number
> of mitochondrial genes which have been transfered to the nuclear DNA?
No, but then there aren't many data points. Also, one would in fact not
expect a detectable correlation, because it seems that the mtDNA genes
which mutate most often are not those for the proteins but those for the
tRNAs, which affect all proteins equally.
> Are there any animals of any kind which have more or less mitochondrial
> genes than the human 13?
Yes, but only just. Nematodes (such as C. elegans) and some mussels have
only 12; the missing one is a very small gene (encoding only 50-odd amino
acids), and as yet we don't in fact know that even that one has actually
been transferred -- it may have been lost altogether.
Aubrey de Grey
