Teresa Binstock (binstoct at essex.UCHSC.edu) wrote:
: On 13 Mar 1996, Keith Robison wrote:
: > Trying to draw a link between yeast mating and human gender determination
: > via GCR isn't particularly compelling; GCR's are ubiquitous.
: >
: However, many yeast genes are homologous to mammalian genes, including
: certain human genes. Some mammalian gene products function similarly in
: yeast, some yeast products function in mammalian tissues.
Yes, no dispute there.
: The fact that
: ste2 and ste3 are expressed in human T cells and perhaps elsewhere
: suggests that there may be some aspect of preserved function.
No, Yeast ste2 and yeast ste3 are not expressed, but rather
members of the GCR family. I am just pointing out that you need
to provide more striking evidence (a GCR tree might do) for there
being reason to expect that the yeast genes are functionally related to
the human genes. A quick BLAST search with STE2 & 3 finds only
other fungal GCRs; there is no special relationship to the
T-cell proteins.
: The fact that most G-protein related events may be ubiquitous does not
: disprove specific examples -- especially given the growing number of
: yeast/human genes known to function similarly in both species.
Of course not; but most (if not all) of those examples are based on
more specific relationships.
: To present an outlandish example: the jury did not find Ted Bundy not
: guilty by virtue of the fact that most white males are not like Ted
: Bundy.
A better example is that I am not suspected of
being a serial killer just because Ted Bundy was; we are both
white males, but that is just about all we have in common on
the face of it. Similarly, STE2/3 and the human proteins have
nothing strikingly in common other than being GCRs. This implies
certain general similarities (membrane bound, acting via a
G-protein effector), but really doesn't say anything about
likely similarities at any higher levels (gender).
Keith Robison
Harvard University
Department of Molecular & Cellular Biology
Department of Genetics
robison at mito.harvard.edu
