Isolation and properties of YCK2, a Saccharomyces cerevisiae homolog of casein kinase-1.
A soluble fragment of YCK2, a casein kinase-1 isoform from Saccharomyces cerevisiae, has been purified and characterized in vitro. The procedure enriches enzyme activity to a final specific activity of 4.7 mumol min-1 mg-1 (when assayed with casein as substrate). Structural analysis reveals that the preparation arises from N-terminal modification and C-terminal proteolysis of the initially synthesized 546-residue protein, consisting of residues 2-495 +/- 1. Kinetic analysis demonstrates that YCK2 is similar to casein kinase-1 isolated from other organisms in its inability to use GTP as nucleotide substrate, in its sensitivity to heparin and ribofuranosyl-benzimidazole inhibitors, and in its peptide substrate selectivity. The enzyme is unusual, however, in that it is insensitive to the potent mammalian casein kinase-1 inhibitor N-(2-aminoethyl)-5-chloroisoquinoline-8-sulfonamide.
Vancura
A
A
Cold Spring Harbor Laboratory, New York 11724-2220.
O'Connor
A
A
Patterson
S D
SD
Mirza
U
U
Chait
B T
BT
Kuret
J
J
D000595:Amino Acid Sequence; D001562:Benzimidazoles / Q000494:pharmacology; D047389:Casein Kinase I; D047388:Casein Kinases; D055598:Chemical Phenomena; D002627:Chemistry, Physical; D004795:Enzyme Stability; D006160:Guanosine Triphosphate / Q000378:metabolism; D006493:Heparin / Q000494:pharmacology; D007546:Isoquinolines / Q000494:pharmacology; D007700:Kinetics; D008969:Molecular Sequence Data; D011494:Protein Kinases / Q000737:chemistry / Q000302:isolation & purification* / Q000378:metabolism; D012441:Saccharomyces cerevisiae / Q000201:enzymology*; D029701:Saccharomyces cerevisiae Proteins; D013379:Substrate Specificity
D001562:Benzimidazoles; D007546:Isoquinolines; D029701:Saccharomyces cerevisiae Proteins; C058815:N-(2-aminoethyl)-5-chloroisoquinoline-8-sulfonamide; D006160:Guanosine Triphosphate; D006493:Heparin; D011494:Protein Kinases; D047389:Casein Kinase I; D047388:Casein Kinases; C479666:YCK2 protein, S cerevisiae