SINGLE CRYSTAL X-RAY DATA COLLECTION FOR PHOSPHOLIPASE AND INHIBITORS

这个子项目是众多研究子项目之一

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. Secreted phospholipase A2 (sPLA2) enzymes regulate cytokine-mediated inflammatory pathways. Exogenous Group IIA sPLA2 (sPLA2-IIA) can enhance tumour necrosis factor (TNF)-stimulated prostaglandin E2 (PGE2) production via the upregulation of NF-B-dependent cyclooxygenase(COX) protein levels in fibroblast-like synovial cells from RA patients1. The activity of cytoplasmic PLA2-(cPLA2-) is required. Proliferation of prostate cancer cells induced by exogenous sPLA2-IIA requires both sPLA2-IIA enzyme activity and cPLA2- activity2. Thus, exogenous sPLA2-IIA modulates cell function by distinct context-dependent mechanisms. We have developed inhibitors that block both the enzymatic and activity independent actions of sPLA2-IIA3 requiring the elucidation of the structure of sPLA2-IIA complexed with our inhibitors. We have grown several different crystal forms of sPLA2-IIA4 in the presence of our inhibitors, a number of which have been solved and refined from several 2.8 Ǻ datasets collected in-house. There is strong evidence of our inhibitors complexed with sPLA2-IIA, however the inhibitor density is not sufficiently well-resolved to determine the precise interactions of our inhibitors from current data. We require high precision, high resolution datasets in order to better define the structure and interactions of the inhibitors and in turn provide valuable insight into the mechanism by which sPLA2-IIA exerts its effects in inflammatory diseases and prostate cancer. 1Bidgood, M.J. et al(2000) J. Immunol. 165, 2790;2Sved, P. et al(2004) Cancer Res. 64, 6934; 3Church, W.B. et al(2001), J. Biol. Chem. 276, 33156; 4Church, W.B. et al(2000),Acta Cryst. D56,1482