HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE ADVANCED SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Citation Map Services Similar articles in this journal Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Google Scholar Google Scholar Articles by Oguri, T. Articles by Inagaki, M. Search for Related Content PubMed PubMed Citation Articles by Oguri, T. Articles by Inagaki, M.

¹ Division of Biochemistry, Aichi Cancer Center Research Institute, Nagoya 464-8681, Japan
² Division of Biochemical Oncology and Immunology, Institute for Genetic Medicine, Hokkaido University, Kita-15, Nishi-7, Kita-ku, Sapporo 060-0815, Japan
³ Division of Cancer Chemotherapy, Miyagi Cancer Center Research Institute, 47-1 Nodayama, Medeshima-Shiode, Natori, Miyagi 981-1293, Japan
⁴ Department of Cell Pharmacology, Graduate School of Medicine, Nagoya University, Tsurumai, Showa-ku, Nagoya, Aichi 466-8550, Japan
⁵ Division of Signal Transduction, Graduate School of Biological Science, Nara Institute of Science and Technology, Ikoma, Nara 630-0192, Japan

In astrocytes, the PGF₂ or ionomycin treatment induces the phosphorylation at Ser38 and Ser82 of vimentin, a type III intermediate filament, by Ca²⁺/calmodulin-dependent protein kinase II (CaMKII). We found here that vimentin phospho-Ser82 was dephosphorylated much slower than phospho-Ser38. Vimentin phospho-Ser38 was dephosphorylated quickly by purified PP1 catalytic subunit (PP1c) in vitro, whereas phospho-Ser82 was insensitive to PP1c. Because PP1c directly bound to vimentin through a VxF motif (Val83-Asp84-Phe85), the PP1c active site appeared to be unable to approach phospho-Ser82, leading to the prolongation of the phosphorylation at Ser-82. In astrocytes, PP1c was in vivo associated with vimentin filaments. The repetitive treatment by ionomycin at a short interval resulted in the sustained elevation of Ser82 phosphorylation, leading to the marked disassembly of vimentin filaments. Taken together, these results suggest that vimentin is a novel member of binding partner of PP1c in astrocytes, and vimentin-Ser82 may act as a memory phosphorylation site.

^* Correspondence: E-mail: minagaki{at}aichi-cc.jp

This article has been cited by other articles:

				S. Kim and P. A. Coulombe Intermediate filament scaffolds fulfill mechanical, organizational, and signaling functions in the cytoplasm Genes & Dev., July 1, 2007; 21(13): 1581 - 1597. [Abstract] [Full Text] [PDF]