Bruce Baker
Title
Professor
Department
Biological Sciences
Research Interests
Control of sexual differentiation, including behavior
Email
bbaker@cmgm.stanford.edu
Phone
723-1843
Fax
723-6035
Address
Herrin Labs Room 305
Mail Code: 5020
Faculty Research Description
Bruce Baker's laboratory is using molecular genetic techniques to dissect
the processes of sex determination, dosage compensation and imaginal disc
development in the fruit fly, Drosophila melanogaster, with the goal of
understanding at a molecular level the functioning of the cascades of
regulatory genes that are responsible for these processes.
Genetic studies showed that a single hierarchy of sex-specific regulatory
genes controls all aspects of somatic sexual differentiation in flies.
Current work on sex determination is focused on the molecular analysis
of these regulatory genes with the aims of understanding how they control
(1) each other's activities in this regulatory cascade and (2) the genes
concerned with sexual differentiation. Of particular interest is our recent
discovery of a gene that functions in a previously unrecognized branch
of the sex determination hierarchy that functions in a small number of
CNS cells to lay down the potential for all aspects of male sexual behavior.
Dosage compensation in flies is achieved by the doubling of the transcription
rate of the genes on the single X chromosome of the male so that it produces
as much product as the two X chromosomes of the female. Research is focused
on how the five genes that regulate this process function to increase
the transcription rate of the male's X chromosome. Molecular and genetic
analyses of these genes suggests that they encode proteins that assemble
into a complex which then binds to the male's X chromosome and increases
its transcription rate. The mechanism by which this occurs is being dissected.
The genital imaginal disc gives rise to the internal and external genitalia
of the adult and thus shows substantial dimorphism in its development
and differentiation. Research in the lab is directed at (1) understanding
at the genetic and molecular levels how the genital disc cells are initially
specified in the embryo; (2) how pattern formation occurs in this disc;
and (3) the processes that drive the morphogenesis of this disc.
Chen, E. H., and Baker, B. S., 1997, Compartmental organization of the
Drosophila genital imaginal discs. Development 124: 205-218.
Bashaw, G. J. and Baker, B. S. 1997. The regulation of the Drosophila
msl-2 gene reveals a function for Sex-lethal in translational control.
Cell 89: 789-798.
Ryner, L. c., Goodwin, S.F., Castrillon, D. H., Anand, A., Villella, A.,
Baker, B. S., Hall, J. C., Taylor, B. T., and S. A. Wasserman. 1996 Control
of male sexual behavior and sexual orientation in Drosophila by the fruitless
gene. Cell 87:1079-1089.
Marín, I., Franke, A., Bashaw, G. J., and Baker, B. S. (1996). Dosage
compensation in flies: a regulatory system adapting to chromosome evolution..
Nature, 383: 160-163.
Oliver, B., Y.-J. Kim, and B.S. Baker. 1993. Sex-lethal, master and slave:
The hierarchy of germline sex determination in Drosophila. Development
119: 897-908.
Areas of Study
Systems/Behavioral Neuroscience
Cellular Neurobiology
Developmental Neuroscience
SBRC
Ph.D.