THE EXPRESSION AND FUNCTION OF IPLA2B IN B-CELLS

该子项目是利用NIH/NCRR资助的中心赠款提供的资源的许多研究子项目之一。子项目和研究者（PI）可能从另一个NIH来源获得了主要资金，因此可以在其他CRISP条目中表示。所列机构为中心机构，不一定是研究者机构。许多细胞表达VIA族磷脂酶A2，命名为iPLA 2B，其不需要钙来活化，由ATP刺激，并且对溴烯醇内酯自杀底物（BEL）的抑制敏感。 在各种细胞系统中的研究已经表明iPLA 2B在磷脂重塑、信号转导、细胞增殖和凋亡中具有作用。我们发现胰岛、B细胞和葡萄糖反应性胰岛素瘤细胞表达iPLA 2B，其参与葡萄糖刺激的胰岛素分泌，但不参与膜磷脂重塑。此外，最近的研究表明，iPLA 2B参与有助于B细胞增殖和凋亡的途径，并且各种磷脂衍生的介质参与这些过程。酶的详细表征表明，B细胞表达多种iPLA 2B亚型，我们假设这些亚型参与不同的细胞功能。

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. Many cells express a Group VIA phospholipase A2, designated iPLA2B, that does not require calcium for activation, is stimulated by ATP, and is sensitive to inhibition by a bromoenol lactone suicide substrate (BEL). Studies in various cell systems have led to the suggestion that iPLA2B has a role in phospholipids remodeling, signal transduction, cell proliferation, and apoptosis. We have found that pancreatic islets, B-cells, and glucose-responsive insulinoma cells express an iPLA2B that participates in glucose-stimulated insulin secretion but is not involved in membrane phospholipids remodeling. Additionally, recent studies reveal that iPLA2B is involved in pathways that contribute to B-cell proliferation and apaptosis, and that various phospholipid-derived mediators are involved in these processes. Detailed characterization of the enzyme suggests that the B-cells express multiple isoforms of iPLA2B, and we hypothesize that these participate in different cellular functions.