Central nervous system development and animal behavior
We study genes that have known or suspected roles in learning and memory processes. At
the molecular level, the goals are to understand the structure, regulation, evolution and biological
function of these genes. At the cellular level, the goal is to understand how the gene products form
an interacting network that alters the physiological state of neurons that mediate behavior. An
additional goal is to understand how alterations in neuronal physiology produce changes in
communication with neighboring neurons that comprise the behavioral circuits.
Several genes important for learning in Drosophila have been studied extensively. Three
of these include include dunce, rutabaga and DCO. Flies carrying lesions in any of these
genes exhibit poor learning in olfactory conditioning tasks. Molecular cloning has demonstrated that
dunce codes for the enzyme, cAMP phosphodiesterase; rutabaga codes for adenylyl cyclase;
and DCO codes for the catalytic subunit of protein kinase A. These results demonstrate that
the cAMP signaling system is critical for altering the physiological state of the neurons that mediate
this type of learning. Other recent studies have shown that interesting cell adhesion molecules of the
integrin family and the immunoglobulin superfamily are important for learning probably by mediating
adhesions or signaling at relevant synapses. Moreover, we have studied several biogenic amine
receptors, including dopamine receptors, that are likely involved in these processes. By studying the
expression of these genes, the neurons that mediate learning have been identified. These are termed
mushroom body cells. Our current goals include understanding these genes in further detail along with
more recently identified genes and studying how these genes interact with one another.
It is important to determine whether these genes also serve mammalian behavior. To approach
this, we have cloned mouse homologs of some of the aforementioned genes and have studied their
expression in the brain. Genetic knockout experiments are being undertaken for those that appear most
promising.
Selected Publications
Davis RL (2001) Mushroom bodies, Ca2+ oscillations, and the
memory gene amnesiac. Neuron 30:653-656.
Cheng Y, Endo K, Wu K, Rodan AR, Heberlein U, Davis RL (2001)
Drosophila fasciclinII is required for the formation of odor memories and for normal sensitivity
to alcohol. Cell 105:757-768.
Roman G, Davis RL (2001) Molecular biology and anatomy of Drosophila
olfactory associative learning. BioEssays 23:571-581.
McGuire SE, Le PT, Davis RL (2001) The role of Drosophila mushroom body
signaling in olfactory memory. Science 293:1330-1333.
Roman G, Endo K, Zong L, Davis RL (2001) P{Switch}, a system for spatial and
temporal control of gene expression in Drosophila melanogaster. Proceedings of the National
Academy of Sciences U.S.A. 98:12602-12607.
Roman G, Davis RL (2002) Conditional expression of UAS-transgenes in the adult eye
with a new gene-switch vector system. Genesis 34:127-131.
Yu D, Baird GS, Tsien RY, Davis RL (2003) Detection of calcium transients in
Drosophila mushroom body neurons with camgaroo reporters. Journal of Neuroscience
23:64-72.
McGuire SE, Le PT, Osborn AJ, Matsumoto K, Davis RL (2003) Spatiotemporal
rescue of memory dysfunction in Drosophila. Science 302:1765-1768.
Mao Z, Roman G, Zong L, Davis, R.L. (2004) Pharmacogenetic rescue in time and
space of the rutabaga memory impairment by using Gene-Switch. Proceedings of the National
Academy of Sciences U.S.A. 101:198-203.
Contact Information
- Ronald L. Davis, Ph.D.
- Department of Molecular and Cellular Biology
- Baylor College of Medicine
- One Baylor Plaza M828
- Houston, Texas 77030, U.S.A.
- Lab Website
- Tel: (713) 798-6641
- Fax: (713) 798-8005
- E-mail: rdavis@bcm.tmc.edu
|
