Dual Specificity Tyrosine Phosphorylation Regulated Kinase 1B (DYRK1B)

DYRK1B is a member of the DYRK family of protein kinases. DYRK1B contains a bipartite nuclear localization signal and is found mainly in muscle and testis. The protein is proposed to be involved in the regulation of nuclear functions. Three isoforms of DYRK1B have been identified differing in the presence of two alternatively spliced exons within the catalytic domain.The putative DYRK1B peptide has a domain structure similar to that of DYRK1A, with a kinase domain flanked by a 110-amino acid N-terminal domain and a 198-amino acid C-terminal domain. Human DYRK1A and DYRK1B proteins are 84% identical in the N-terminal and catalytic domains but show no extended similarity in the C-terminal region. Northern blot analysis detected a 2.4-kb DYRK1B transcript in testis and skeletal muscle.