Calcium-dependent, phospholipid-binding proteins associate with biological membranes in response to cell activation and calcium entry into the cytoplasm. The goal of this project is to determine the structures and biological activities of two ubiquitous classes of these proteins, the annexins, and C2-domain containing proteins. X-ray crystallography will be used to determine the structures of annexin II, the cytoplasmic domain of synaptotagmin, and the copines. Electron microscopy of 2-dimensional crystals of these proteins on lipid monolayers will be used to determine the physical nature of the interaction of these proteins with membranes. The role of individual protein domains in promoting lipid interaction and specificity will be determined by mutagenesis of the proteins and studies on model membrane systems. Proteins that interact with and are regulated by the annexins and copines will be characterized. The localization and movements of these membrane-binding proteins in living cells and tissues will be determined. The functions of the annexins and copines will be studied by genetic silencing methods in two model organisms, the nematode C. elegans, and the ciliate Paramecium tetaurelia. These peripheral proteins are hypothesized to mediate or regulate events occurring on membrane surfaces in stimulated cells. Therefore, these studies should provide insights into basic mechanisms underlying the regulation of membrane trafficking and signal transduction across membranes occurring in normal cells and in pathological conditions including cancer, neurogenic hypertension, diabetes and other endocrine disorders.

Agency
National Institute of Health (NIH)
Institute
National Institute of General Medical Sciences (NIGMS)
Type
Research Project (R01)
Project #
5R01GM053266-07
Application #
6386220
Study Section
Biophysical Chemistry Study Section (BBCB)
Program Officer
Chin, Jean
Project Start
1995-07-01
Project End
2003-06-30
Budget Start
2001-07-01
Budget End
2002-06-30
Support Year
7
Fiscal Year
2001
Total Cost
$250,137
Indirect Cost
Name
University of Virginia
Department
Pharmacology
Type
Schools of Medicine
DUNS #
001910777
City
Charlottesville
State
VA
Country
United States
Zip Code
22904
Creutz, C E; Snyder, S L; Schulz, T A (2004) Characterization of the yeast tricalbins: membrane-bound multi-C2-domain proteins that form complexes involved in membrane trafficking. Cell Mol Life Sci 61:1208-20
Sohma, H; Creutz, C E; Gasa, S et al. (2001) Differential lipid specificities of the repeated domains of annexin IV. Biochim Biophys Acta 1546:205-15
Daigle, S N; Creutz, C E (1999) Transcription, biochemistry and localization of nematode annexins. J Cell Sci 112 ( Pt 12):1901-13
Sohma, H; Creutz, C E; Saitoh, M et al. (1999) Characterization of the Ca2+-dependent binding of annexin IV to surfactant protein A. Biochem J 341 ( Pt 1):203-9