This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. Primary support for the subproject and the subproject's principal investigator may have been provided by other sources, including other NIH sources. The Total Cost listed for the subproject likely represents the estimated amount of Center infrastructure utilized by the subproject, not direct funding provided by the NCRR grant to the subproject or subproject staff. Actin makes different structures throughout cells including a branched actin network at the leading edge of motile cells, parallel actin bundles in filopodia, and actomyosin contractile apparatus during cytokinesis. Tropomyosin participates in many of these structures by controlling access to the actin filament. Much is known about tropomyosin's role in muscle contraction, but much less is understood about its role in nonmuscle cells. It is difficult to study tropomyosin in nonmuscle cells because higher eukaryotes can express up to forty different splice variants from four different genes with up to seven isoforms expressed in any one nonmuscle cell type. This isoform diversity makes it difficult to tease out the contributions of each tropomyosin type. The key to solving the mystery of nonmuscle tropomyosin is finding a simple model organism with a minimal number of nonmuscle tropomyosin isoforms that can be individually studied. Drosophila melanogaster seems to be perfect for this task because only one nonmuscle tropomyosin isoform is known to identify the additional nonmuscle isoform(s) have been inconclusive. We believe the UCSF Mass Spectrometry Facility can help us identify the unknown nonmuscle tropomyosin isoforms. We plan to partially isolate native tropomyosin from Drosophila nonmuscle cells (S2 cells), identify the protein sequence using mass spectrometry, and then characterize the isoforms in vitro an in living S2 cells. These studies will help elucidate the role of tropomyosin isoform diversity in nonmuscle cells.

National Institute of Health (NIH)
National Center for Research Resources (NCRR)
Biotechnology Resource Grants (P41)
Project #
Application #
Study Section
Special Emphasis Panel (ZRG1-BCMB-M (40))
Project Start
Project End
Budget Start
Budget End
Support Year
Fiscal Year
Total Cost
Indirect Cost
University of California San Francisco
Schools of Pharmacy
San Francisco
United States
Zip Code
Twiss, Jeffery L; Fainzilber, Mike (2016) Neuroproteomics: How Many Angels can be Identified in an Extract from the Head of a Pin? Mol Cell Proteomics 15:341-3
Julien, Olivier; Zhuang, Min; Wiita, Arun P et al. (2016) Quantitative MS-based enzymology of caspases reveals distinct protein substrate specificities, hierarchies, and cellular roles. Proc Natl Acad Sci U S A 113:E2001-10
Cil, Onur; Phuan, Puay-Wah; Lee, Sujin et al. (2016) CFTR activator increases intestinal fluid secretion and normalizes stool output in a mouse model of constipation. Cell Mol Gastroenterol Hepatol 2:317-327
Kintzer, Alexander F; Stroud, Robert M (2016) Structure, inhibition and regulation of two-pore channel TPC1 from Arabidopsis thaliana. Nature 531:258-62
Bongrand, Clotilde; Koch, Eric J; Moriano-Gutierrez, Silvia et al. (2016) A genomic comparison of 13 symbiotic Vibrio fischeri isolates from the perspective of their host source and colonization behavior. ISME J 10:2907-2917
Bikle, Daniel D (2016) Extraskeletal actions of vitamin D. Ann N Y Acad Sci 1376:29-52
Bradshaw, J Michael; McFarland, Jesse M; Paavilainen, Ville O et al. (2015) Prolonged and tunable residence time using reversible covalent kinase inhibitors. Nat Chem Biol 11:525-31
Correia, Maria Almira; Wang, YongQiang; Kim, Sung-Mi et al. (2014) Hepatic cytochrome P450 ubiquitination: conformational phosphodegrons for E2/E3 recognition? IUBMB Life 66:78-88
Wiita, Arun P; Seaman, Julia E; Wells, James A (2014) Global analysis of cellular proteolysis by selective enzymatic labeling of protein N-termini. Methods Enzymol 544:327-58
Tajon, Cheryl A; Seo, Daeha; Asmussen, Jennifer et al. (2014) Sensitive and selective plasmon ruler nanosensors for monitoring the apoptotic drug response in leukemia. ACS Nano 8:9199-208

Showing the most recent 10 out of 619 publications