A cdc2-related kinase PSSALRE/cdk5 is homologous with the 30 kDa subunit of tau protein kinase II, a proline-directed protein kinase associated with microtubule.
We previously reported that tau protein kinase II (TPKII) from bovine brain was composed of 30 kDa and 23 kDa subunits. The 30 kDa subunit of TPKII can be regarded as a catalytic subunit because of its ATP-binding activity. Antibodies directed against TPKII-phosphorylated tau also reacted with tau phosphorylated by cdc2 kinase obtained from starfish oocytes, indicating that TPKII and cdc2 kinase phosphorylate the same sites. We determined the amino acid sequence of the 30 kDa subunit and found it to be homologous with a cdc2-related kinase, PSSALRE/cdk5. Moreover, an antibody against PSSALRE/cdk5 reacted with the 30 kDa subunit. These results indicate that the 30 kDa subunit of TPKII is bovine homologue of PSSALRE/cdk5. Expression of the 30 kDa subunit mRNA was enhanced in juvenile rat brain. This result supports our previous hypothesis that the kinase works actively in juvenile brain.
Kobayashi
S
S
Mitsubishi Kasei Institute of Life Sciences, Tokyo, Japan.
Ishiguro
K
K
Omori
A
A
Takamatsu
M
M
Arioka
M
M
Imahori
K
K
Uchida
T
T
D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D016203:CDC2 Protein Kinase / Q000737:chemistry; D002417:Cattle; D051360:Cyclin-Dependent Kinase 5; D018844:Cyclin-Dependent Kinases; D018076:DNA, Complementary; D006801:Humans; D008870:Microtubules / Q000201:enzymology*; D008969:Molecular Sequence Data; D011392:Proline / Q000378:metabolism*; D011494:Protein Kinases / Q000737:chemistry* / Q000378:metabolism; D017346:Protein Serine-Threonine Kinases / Q000737:chemistry* / Q000378:metabolism; D051381:Rats; D017386:Sequence Homology, Amino Acid; D016875:tau Proteins / Q000378:metabolism
D018076:DNA, Complementary; D016875:tau Proteins; D011392:Proline; D011494:Protein Kinases; D051360:Cyclin-Dependent Kinase 5; D017346:Protein Serine-Threonine Kinases; D016203:CDC2 Protein Kinase; C495905:CDK5 protein, human; C495907:Cdk5 protein, rat; D018844:Cyclin-Dependent Kinases; C079134:tau protein kinase II