?
![Click on image for an interactive view with Cn3D](cdThumbnail.cgi?uid=271128)
Catalytic domain of the protein kinase, Dual-specificity tYrosine-phosphorylated and -Regulated Kinase 1 Dual-specificity PKs catalyze the transfer of the gamma-phosphoryl group from ATP to serine/threonine (S/T) as well as tyrosine residues on protein substrates. Mammals contain two types of DYRK1 proteins, DYRK1A and DYRK1B. DYRK1A was previously called minibrain kinase homolog (MNBH) or dual-specificity YAK1-related kinase. It phosphorylates various substrates and is involved in many cellular events. It phosphorylates and inhibits the transcription factors, nuclear factor of activated T cells (NFAT) and forkhead in rhabdomyosarcoma (FKHR). It regulates neuronal differentiation by targetting CREB (cAMP response element-binding protein). It also targets many endocytic proteins including dynamin and amphiphysin and may play a role in the endocytic pathway. The gene encoding DYRK1A is located in the DSCR (Down syndrome critical region) of human chromosome 21 and DYRK1A has been implicated in the pathogenesis of DS. DYRK1B, also called minibrain-related kinase (MIRK), is highly expressed in muscle and plays a critical role in muscle differentiation by regulating transcription, cell motility, survival, and cell cycle progression. It is overexpressed in many solid tumors where it acts as a tumor survival factor. DYRKs autophosphorylate themselves on tyrosine residues and phosphorylate their substrates exclusively on S/T residues. The DYRK1 subfamily is part of a larger superfamily that includes the catalytic domains of other STKs, protein tyrosine kinases, RIO kinases, aminoglycoside phosphotransferase, choline kinase, and phosphoinositide 3-kinase.
|