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Cited by 381

The DOI matches its Crossref record; 47 of the 47 references it cites were found in a registry or an index.

Calpain-dependent Proteolytic Cleavage of the p35 Cyclin-dependent Kinase 5 Activator to p25

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Kusakawa, Gen-ichi, Saito, Taro, Onuki, Reiko, Ishiguro, Koichi, Kishimoto, Takeo, Hisanaga, Shin-ichi·2000·Journal of Biological Chemistry

Abstract

Cyclin-dependent kinase 5 (CDK5) is a unique CDK, the activity of which can be detected in postmitotic neurons. To date, CDK5 purified from mammalian brains has always been associated with a truncated form of the 35-kDa major brain specific activator (p35, also known as nck5a) of CDK5, known as p25. In this study, we report that p35 can be cleaved to p25 both in vitro and in vivo by calpain. In a rat brain extract, p35 was cleaved to p25 by incubation with Ca(2+). This cleavage was inhibited by a calpain inhibitor peptide derived from calpastatin and was ablated by separating the p35.CDK5 from calpain by centrifugation. The p35 recovered in the pellet after centrifugation could then be cleaved to p25 by purified calpain. Cleavage of p35 was also induced in primary cultured neurons by treatment with a Ca(2+) ionophore and Ca(2+) and inhibited by calpain inhibitor I. The cleavage changed the solubility of the CDK5 active complex from the particulate fraction to the soluble fraction but did not affect the histone H1 kinase activity. Increased cleavage was detected in cultured neurons undergoing cell death, suggesting a role of the cleavage in neuronal cell death.

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Metadata

Authors
Kusakawa, G.-I., Saito, T., Onuki, R., Ishiguro, K., Kishimoto, T., & Hisanaga, S.-I.
Venue
Journal of Biological Chemistry
Publisher
Elsevier BV
Published
2000-06
Volume
275
Issue
22
Pages
17166-17172
ISSN
0021-9258 (ISSN-L)
OpenAlex
W1979014608
Cited by
381
References
47
FWCI
8.62
Type
journal article
Language
en
Open access
hybrid

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CoChat. (2026). Citation check: Calpain-dependent Proteolytic Cleavage of the p35 Cyclin-dependent Kinase 5 Activator to p25. https://app.cochat.ai/papers/10.1074/jbc.m907757199
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Kusakawa, G.-I., Saito, T., Onuki, R., Ishiguro, K., Kishimoto, T., & Hisanaga, S.-I. (2000). Calpain-dependent Proteolytic Cleavage of the p35 Cyclin-dependent Kinase 5 Activator to p25. Journal of Biological Chemistry. https://doi.org/10.1074/jbc.m907757199

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