Re: What is the difference between yeast strain ?
Hi There!
I am a newer in yeast but working on the yeast two hybrid system for almost
three years. A lot of exciting data gave me a big picture about the cross
talking among the proteins I am interested in. But one interaction bother me
for a while. I guess this might be a potential problem or could be a
commo-problem in the future using yeast two hybrid system.
1. I detected the interaction between Protein A and Protein B in Yeast strain,
PCY2. The b-galactosidase activity induced by this interaction is beatiful.
2. Since some other strains have been developed (esp. using his and gal for
double selection), I tried one. All positive are positive,and all negative are
negative. Most interaction in my work showed positive. But A-B interaction
showed negative (both in his and b-galactosidase).
3. I made a conclusion that there is no direct A-B interaction but a complex
containing A and B is formed, and the A-B complex is medicated by other
factors.
Above is the experiment and conclusion. It appears to be perfect to tell this
story in my next publication. But, as I said, I am an user not a "yeastist".
So I basically want ask myself and "yeastists" three questions.
1. Is the difference between strains enough to giving these difference? I
understand that the difference between two animal cells might be trillion. Can
some one tell me at what level the yeast strains show difference?
2. Am I so lucky to find this complex but an indirect interaction by using the
second strain, which I pick randomly "one day"?
3. Obiviously, one like to know what is the third factor(s) mediating this
interaction. Any suggestion to provide that there is such factor(s) before I
screening the yeast library (beacuse the screen is not the first choice, at
least for me)?
Any suggestion or comments are appreactiated. If this is a true problem in the
using of two hybrid system, I wish this should be paid attention to. The
false-positive might means more than what we thought.
By the way, I can read "yeast-net" through gopher. You can send mail to me or
"yeast-net".
Thanks again!
Hong F. Wang
Department of Cell Biology, Neurobiology, and Anatomy
University of CIncinnati College of Medicine
231 Bethesda Ave.
Cincinnati, OH 45267-0521
Phone: (513)558-6787
Fax: (513)558-4454
E-mail: wangho at ucbeh.san.uc.edu
