Hematopoietic lineage cell specific protein 1 associates with and down-regulates protein kinase CK2.
The catalytic (alpha) subunit of protein kinase CK2 and the hematopoietic specific protein 1 (HS1) display opposite effects on Ha-ras induced fibroblast transformation, by enhancing and counteracting it, respectively. Here we show the occurrence of physical association between HS1 and CK2alpha as judged from both far Western blot and plasmon resonance (BIAcore) analysis. Association of HS1 with CK2alpha is drastically reduced by the deletion of the HS1 C-terminal region (403-486) containing an SH3 domain. HS1, but not its deletion mutant HS1 Delta324-393, lacking a sequence similar to an acidic stretch of the regulatory beta-subunit of CK2, inhibits calmodulin phosphorylation by CK2alpha. These data indicate that HS1 physically interacts with CK2alpha and down-regulates its activity by a mechanism similar to the beta-subunit.
Ruzzene
M
M
Dipartimento di Chimica Biologica and Centro per lo Studio delle Biomembrane del CNR, University of Padova, Viale G. Colombo, 335121, Padova, Italy.
Brunati
A M
AM
Sarno
S
S
Donella-Deana
A
A
Pinna
L A
LA
D048868:Adaptor Proteins, Signal Transducing; D000595:Amino Acid Sequence; D017209:Apoptosis; D001798:Blood Proteins / Q000235:genetics* / Q000378:metabolism*; D015153:Blotting, Western; D002147:Calmodulin / Q000378:metabolism; D047390:Casein Kinase II; D015536:Down-Regulation; D004926:Escherichia coli / Q000378:metabolism; D006801:Humans; D007700:Kinetics; D008969:Molecular Sequence Data; D016296:Mutagenesis; D010455:Peptides / Q000378:metabolism; D010766:Phosphorylation; D017346:Protein Serine-Threonine Kinases / Q000235:genetics* / Q000378:metabolism*; D017386:Sequence Homology, Amino Acid; D020349:Surface Plasmon Resonance; D013997:Time Factors; D014162:Transfection
D048868:Adaptor Proteins, Signal Transducing; D001798:Blood Proteins; D002147:Calmodulin; C061909:HCLS1 protein, human; D010455:Peptides; D047390:Casein Kinase II; D017346:Protein Serine-Threonine Kinases