cmpidgeo at ucalgary.ca
Thu Jul 6 17:25:13 EST 2000
A very good general reference is Soltis DE, Soltis PS (2000)
Contributions of plant molecular systematics to studies of molecular
evolution. Plant Molecular Biology 42:45-75.
It has a very good list of references that may help.
Obviously genes that encode for essential proteins will be more
conserved. In some cases genes involved in secondary metabolism are
present only in specific plant species (a good example is opium
biosynthetic genes in Poppy).
The degree of taxonomic similarity of based on orthologous sequences is
difficult since it really depends on how you do the phylogeny and how
related the genes are. In some cases, genes that are very closely
related do not yield reliable phylogenies. This also depends on whether
you are looking at protein or nucleic acid data.
For many genes, heterologous probes can often be used to isolate from
different species but it all depends. It is easy to try a few membranes
at a couple of different temperatures. If that doesn't work you can
always try a PCR approach with degenerate primers.
Hope this helps,
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