cDNA clones for a fifth polypeptide of rat brain calmodulin-dependent protein kinase II were isolated and sequenced. The cDNA sequence encoded a polypeptide, designated δ, consisting of 533 amino acid residues with a molecular weight of 60,080. Comparison of amino acid sequences of this and α, β, β', and γ polypeptides of calmodulin-dependent protein kinase II reveals marked homology among them. The mRNAs for δ were expressed in rat brain tissues with different regional specifities. The distribution of α,β/β', γ, and δ mRNAs in cerebrum, skeletal muscle, diaphragm, hear, small intestine, uterus, aorta, liver, kidney, lung, and testis were examined by RNA blot hybridization analysis with probes specific for the respective mRNAs. A 3.9-kilobase (kb) RNA species hybridizable with a probe for γ was found in all the tissues examined, and 4.0-4.2-kb RNA species hybdridizable with a probe for δ were found in all the tissues examined except for liver, while a 4.8-kb RNA species hybridizable with a probe for α and a 4.2-kb RNA species hybridizable with a probe for β were present in brain but not in the other tissues. With the α probe, however, a 4.1- and 2.6-kb RNA species were both detected in skeletal muscle and diaphragm. With the β probe, a 4.3-kb RNA in skeletal muscle and diaphragm, 2.9-kb RNA in small intestine, and 4.0-kb RNA in testis were detected. With the δ probe, a 3.5-kb RNA in heart and 1.8-kb RNA in testis were detected. Thus, γ and δ mRNAs were expressed in various tissues, while α and β/β' mRNAs were primarily, if not exclusively, expressed in brain.
|Number of pages||6|
|Journal||Journal of Biological Chemistry|
|Publication status||Published - Jan 1 1989|
ASJC Scopus subject areas
- Molecular Biology
- Cell Biology