Autor: Renata Kowara, Andrzej Matecki, Tadeusz Pawelczyk
Rok vydání: 2000
Předmět:
Zdroj: Molecular and Cellular Biochemistry. 209:69-77
ISSN: 0300-8177
DOI: 10.1023/a:1007063331593
Popis: Protein kinase C-γ (PKC-γ) contains two cysteine-rich regions (Cys1, Cys2) responsible for interaction with phospholipids. However, previous experiments suggested that, only Cys1 represents the high affinity site involved in diacylglycerol-dependent activation of PKC-γ. This raises the question whether Cys2 might participate in other functions of the PKC-γ regulatory domain. The purpose of our studies was to examine the ability of Cys2 domain to bind cellular proteins. The Cys2 domain (residues 92-173) was expressed as a fusion protein with glutathione-S-transferase (GST) in Escherichia coli and purified. In order to investigate protein-protein interaction of Cys2 domain we used affinity column and an overlay assay. Our results demonstrate that the Cys2 domain of PKC-γ binds several proteins from rat brain extracts. In the absence of phospholipids the Cys2 domain binds some proteins in the cytosolic fraction of rat brain, but no binding was detected with the proteins extracted from particulate fraction. Ca2+ at 1 μM concentration potentiated binding of cellular proteins to Cys2 domain. In the absence of Ca2+ the Cys2 domain binds proteins in the cytosolic fraction of rat brain in the presence of phosphatidylserine and to the lesser extend in the presence of phosphatidylinositol but neither phosphatidylcholine nor phosphatidylethanolamine.
Databáze: OpenAIRE
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