The PIM-2 kinase phosphorylates BAD on serine 112 and reverses BAD-induced cell death

J Biol Chem. 2003 Nov 14;278(46):45358-67. doi: 10.1074/jbc.M307933200. Epub 2003 Sep 3.

Abstract

Hematopoietic growth factors mediate the survival and proliferation of blood-forming cells, but the mechanisms through which these proteins produce their effects are incompletely known. Recent studies have identified the pim family of kinases as mediators of cytokine-dependent survival signals. Several studies have identified substrates for the pim-1 kinase, but little is known about the other family members, pim-2 and pim-3. We have investigated potential functions for the pim-2 kinase in factor-dependent murine hematopoietic cells. We find that pim-2 mRNA and protein expression are regulated by cytokines similarly to pim-1. Three PIM-2 protein isoforms are produced in cytokine-treated cells. All three forms are active kinases, and the short (PIM-2(34 kDa)) form is the most active at enhancing survival of FDCP1 cells after cytokine withdrawal. This pro-survival function involves inhibition of apoptosis and caspase activation. Enforced expression of PIM-2(34 kDa) kinase does not appear to regulate expression of BCL-2, BCL-xL, BIM, or BAX proteins. However, the kinase can phosphorylate the pro-apoptotic protein BAD on serine 112, which accounts in part for its ability to reverse Bad-induced cell death. Our results indicate that pim-2 functions similarly to pim-1 as a pro-survival kinase and suggest that BAD is a legitimate PIM-2 substrate.

Publication types

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

MeSH terms

  • Animals
  • Antibodies, Monoclonal / metabolism
  • Apoptosis*
  • Blotting, Northern
  • Blotting, Western
  • Carrier Proteins / metabolism*
  • Cell Line
  • Cell Line, Tumor
  • Cell Survival
  • Cycloheximide / pharmacology
  • Cytokines / metabolism
  • DNA, Complementary / metabolism
  • Glutathione Transferase / metabolism
  • HeLa Cells
  • Humans
  • Interleukin-3 / metabolism
  • Jurkat Cells
  • Kinetics
  • Mice
  • NIH 3T3 Cells
  • Phosphorylation
  • Plasmids / metabolism
  • Protein Isoforms
  • Protein Serine-Threonine Kinases*
  • Protein Synthesis Inhibitors / pharmacology
  • Proto-Oncogene Proteins / metabolism*
  • RNA, Messenger / metabolism
  • Serine / chemistry*
  • Time Factors
  • Transfection
  • Transgenes
  • bcl-Associated Death Protein

Substances

  • Antibodies, Monoclonal
  • BAD protein, human
  • Bad protein, mouse
  • Carrier Proteins
  • Cytokines
  • DNA, Complementary
  • Interleukin-3
  • PIM2 protein, human
  • Pim2 protein, mouse
  • Protein Isoforms
  • Protein Synthesis Inhibitors
  • Proto-Oncogene Proteins
  • RNA, Messenger
  • bcl-Associated Death Protein
  • Serine
  • Cycloheximide
  • Glutathione Transferase
  • Protein Serine-Threonine Kinases