Activation of Ca2+/calmodulin-dependent protein kinase II and phosphorylation of intermediate filament proteins by stimulation of glutamate receptors in cultured rat cortical astrocytes

S. Yano, K. Fukunaga, Y. Ushio, E. Miyamoto

Research output: Contribution to journalArticle

67 Citations (Scopus)

Abstract

We investigated the activation of Ca2+/calmodulin-dependent protein kinase II (CaM kinase II) via stimulation of glutamate receptors and subsequent phosphorylation of vimentin and glial fibrillary acidic protein (GFAP) in cultured rat cortical astrocytes. The indirect immunofluorescence analysis with the anti-CaM kinase II antibody revealed that the enzyme was detected diffusely in the cytoplasm and more intensely in the nucleus. Glutamate elevated the Ca2+-independent activity of CaM kinase II through autophosphorylation, and this response was blocked by both DL-2-amino-3- phosphonopropionate and 6-cyano-7-nitroquinoxaline-2,3-dione, but not by D- 2-amino-5-phosphonovalerate. In the experiments using 32P-labeled astrocytes, the phosphorylation of vimentin and GFAP as well as autophosphorylation of CaM kinase II were found to be stimulated after the exposure to glutamate. It was concluded by two-dimensional phosphopeptide analysis that the increased phosphorylation of vimentin and GFAP observed in intact cells were due to the activation of CaM kinase II by glutamate. These results suggest that glutamate can activate CaM kinase II through stimulation of both the metabotropic and non-N-methyl-D-aspartate receptors, and that the concomitant phosphorylation of vimentin and GFAP may in turn regulate the functions of intermediate filament proteins in intact astrocytes.

Original languageEnglish
Pages (from-to)5428-5439
Number of pages12
JournalJournal of Biological Chemistry
Volume269
Issue number7
Publication statusPublished - 1994 Jan 1
Externally publishedYes

ASJC Scopus subject areas

  • Biochemistry
  • Molecular Biology
  • Cell Biology

Fingerprint Dive into the research topics of 'Activation of Ca<sup>2+</sup>/calmodulin-dependent protein kinase II and phosphorylation of intermediate filament proteins by stimulation of glutamate receptors in cultured rat cortical astrocytes'. Together they form a unique fingerprint.

  • Cite this