DYRK1B Antibody #2703

The DYRK family includes several dual-specificity tyrosine-phosphorylated and regulated kinases capable of phosphorylating proteins at both Tyr and Ser/Thr residues (1). The DYRK family was identified based on homology to the yeast Yak1 (2) and the Drosophila minibrain (mnb) kinases (3). Seven mammalian isoforms have been discovered, including DYRK1A, DYRK1B, DYRK1C, DYRK2, DYRK3, DYRK4, and DYRK4B. Differences in substrate specificity, expression, and subcellular localization are seen across the DYRK family (4,5). All DYRK proteins have a Tyr-X-Tyr motif in the catalytic domain activation loop; phosphorylation of the second Tyr residue (e.g. Tyr312 of DYRK1A) is necessary for kinase activity. DYRKs typically autophosphorylate the Tyr residue within their activation loop, but phosphorylate substrates at Ser and Thr residues (1,6).
In contrast to the ubiquitous DYRK1A, DYRK1B exhibits relatively restricted expression with highest levels found in the testis and muscle (7,8). Three major DYRK1B splice variants demonstrate distinct expression patterns and functional properties (9). DYRK1B plays a critical role in myoblast differentiation by affecting cell motility, transcription, cell cycle progression and survival (10,11). In addition, DYRK1B contributes to the survival of certain cancer cells (7,12,13).