Thomas F. J. Martin

 

 

Molecular Mechanisms of Neurotransmitter and Peptide Hormone Secretion

E-mail: tfmartin@wisc.edu

Research Strengths: Membrane Excitability and Synaptic Transmission, Molecular Neuroscience

Our research focuses on the molecular mechanisms responsible for Ca2+-dependent secretion in neural and endocrine cells. Neurotransmitter, neuropeptide and peptide hormone secretion is dependent on Ca2+ influx or mobilization, which triggers secretory vesicle fusion with the plasma membrane. Biochemical, molecular biological and cell biological approaches are utilized to identify key proteins that mediate membrane fusion and its regulation by Ca2+. Current efforts are directed at: 1. the mechanism by which a novel cytosolic protein CAPS facilitates Ca2+-dependent membrane fusion; 2. elucidating the essential role of phospholipid phosphorylation in secretory mechanisms; and 3. understanding the mechanisms by which a Ca2+ sensor (synaptotagmin) controls the membrane fusion machinery (SNAREs).

Website:

http://www.biochem.wisc.edu/martin/

Selected Publications:

• Gerona, R.R.L., E.C. Larsen, J.A. Kowalchyk, and T.F.J. Martin. 2000. The C terminus of SNAP-25 is essential for Ca2+-dependent binding of synaptotagmin to SNARE complexes. J. Biol. Chem. 275: 6328-6336. [PDF]
• Desai, R.C., B. Vyas, C.A. Earles, J.T. Littleton, J. A. Kowalchyk, T.F.J. Martin, and E.R. Chapman. 2000. The C2B domain of synaptotagmin is a Ca2+-sensing module essential for exocytosis. J. Cell Biol. 150: 1125-1135. [PDF]
• Berwin, B., E. Floor, and T.F.J. Martin. 1998. CAPS (mammalian UNC-31) protein localizes to membranes involved in dense-core vesicle exocytosis. Neuron 21: 137-145. [PDF]