A novel, calcium-inhibitable casein kinase in Paramecium cells

This is the first identification of a Ca 2+-inhibitable casein kinase (CPK) which we have isolated from the 100 000× g supernatant of Paramecium cell homogenates. The 1000-fold enriched CPK activity depends on millimolar Mg 2+ and is inhibited by low concentrations of heparin or by ≥100 μM Ca 2+. En...

Full description

Saved in:
Bibliographic Details
Published in:FEBS letters 1997-02, Vol.402 (2), p.227-235
Main Authors: Kissmehl, Roland, Treptau, Tilman, Hauser, Karin, Plattner, Helmut
Format: Article
Language:English
Subjects:
Amino Acid Sequence
Animals
Brain - metabolism
Calcineurin
calcineurin or protein phosphatase-2B
Calcium - pharmacology
Calmodulin
Calmodulin-Binding Proteins - metabolism
CaM
cAMP-dependent protein kinase
CaN
CaN A
CaN B
Casein kinase
casein kinase isolated from P. tetraurelia
Casein Kinases
catalytic subunit of CaN
Cations, Divalent - pharmacology
Cattle
cGMP-dependent protein kinase
Chromatography, Affinity
Chromatography, DEAE-Cellulose
Chromatography, Ion Exchange
CK-1
CK-2
CPK
Egtazic Acid - pharmacology
Exocytosis
exocytosis-sensitive phosphoprotein of 63 kDa
Freshwater
homogenization medium
Kinetics
N-p-tosyl-l-arginine methyl ester
Oligopeptides
PAGE
Paramecium
Paramecium tetraurelia - enzymology
Phosphoprotein Phosphatases - metabolism
Phosphorylation
PKA
PKG
PLA
PLL
poly(l-arginine)
poly(l-lysine)
polyacrylamide gel electrophoresis
PP63
Protein Kinases - isolation & purification
Protein Kinases - metabolism
regulatory subunit of CaN
spermine
Substrate Specificity
TAME
type 1 casein kinase
type 2 casein kinase
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:This is the first identification of a Ca 2+-inhibitable casein kinase (CPK) which we have isolated from the 100 000× g supernatant of Paramecium cell homogenates. The 1000-fold enriched CPK activity depends on millimolar Mg 2+ and is inhibited by low concentrations of heparin or by ≥100 μM Ca 2+. Enzyme activity is stimulated by polylysine or polyarginine with either casein or with specific casein kinase-2 (CK-2) peptide substrates (RRRDDDSDDD and RREEETEEE). The enzymic properties are similar with GTP instead of ATP. CPK does not undergo autophosphorylation. In gel kinase assays, enzyme activity is associated with a 36 kDa band. Calmodulin as another characteristic substrate for mammalian CK-2 has not been phosphorylated by this protein kinase. Besides casein, CPK phosphorylates in vitro the catalytic subunit of bovine brain calcineurin (CaN), a typical substrate of type 1 mammalian casein kinase (CK-1) in vitro. Again this phosphorylation is significantly reduced by Ca 2+. Thus, CPK combines aspects of different casein kinases, but it is clearly different from any type known by its Ca 2+ inhibition. Since CPK also phosphorylates the exocytosis-sensitive phosphoprotein, PP63, in Paramecium, which is known to be dephosphorylated by CaN, an antagonistic Ca 2+-effect during phosphorylation/dephosphorylation cycles may be relevant for exocytosis regulation.
ISSN:0014-5793
1873-3468
DOI:10.1016/S0014-5793(96)01539-6