The expression and function of a group VIA calcium-independent phospholipase A2 (iPLA2beta) in beta-cells

Can J Physiol Pharmacol. 2004 Oct;82(10):824-32. doi: 10.1139/y04-064.

Abstract

Many cells express a Group VIA phospholipase A2, designated iPLA2beta, 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 iPLA2beta has a role in phospholipid remodeling, signal transduction, cell proliferation, and apoptosis. We have found that pancreatic islets, beta-cells, and glucose-responsive insulinoma cells express an iPLA2beta that participates in glucose-stimulated insulin secretion but is not involved in membrane phospholipid remodeling. Additionally, recent studies reveal that iPLA2beta is involved in pathways that contribute to beta-cell proliferation and apoptosis, and that various phospholipid-derived mediators are involved in these processes. Detailed characterization of the enzyme suggests that the beta-cells express multiple isoforms of iPLA2beta, and we hypothesize that these participate in different cellular functions.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.
  • Review

MeSH terms

  • Amino Acid Sequence / genetics
  • Animals
  • Gene Expression Regulation, Enzymologic / physiology*
  • Group VI Phospholipases A2
  • Humans
  • Islets of Langerhans / cytology
  • Islets of Langerhans / metabolism*
  • Molecular Sequence Data
  • Phospholipases A / biosynthesis*
  • Phospholipases A / genetics
  • Phospholipases A2

Substances

  • Phospholipases A
  • Group VI Phospholipases A2
  • PLA2G6 protein, human
  • Phospholipases A2