Casein kinase 2, alpha 1
Protein and coding gene in humans
From Wikipedia, the free encyclopedia
Casein kinase II subunit alpha 1 (CK2α) is an enzyme that in humans is encoded by the CSNK2A1 gene, located on chromosome 20.[5][6]
CK2α is the alpha catalytic subunit of Casein kinase II (CK2). CK2 is a serine/threonine protein kinase that phosphorylates acidic proteins such as casein. The kinase exists in monomeric form and as a tetramer and is composed of two α or α' (alpha prime) subunits and two β subunits; the CK2 holoenzyme has α2β2 stoichiometry.[7][8] The alpha subunits contain the catalytic activity while the beta subunits undergo autophosphorylation. The protein encoded by this gene represents the alpha subunit. Three transcript variants encoding two different proteins have been found for this gene.[9] CK2α' paralog is encoded by the CSNK2A2 gene; it differs in the length and sequence of the C-terminus of the protein.[10]
Gene Location
The CSNK2A1 gene is located on chromosome 20 in humans. In 2025, analyses revealed that CSNK2A1 has 14 exons (rather than 13 exons as previously reported).[11] Protein translation begins 110 nucleotides into exon 3; exons 1 and 2 are entirely untranslated.[12] CSNK2A1 mRNA contains 12,984 nucleotides (coding sequence is 1,176 nucleotides), spanning approximately 71 kb.[11] CSNK2A1 contains 391 amino acids.[13]
Function
CK2α has been implicated in many diseases including cancer, autoimmune disorders, COVID-19, psychiatric disorders, ophthalmic diseases, obesity, diabetes, cardiovascular disorders, neurological disorders, and most recently, Okur-Chung Neurodevelopmental Syndrome (OCNDS).[14] It has roles in cell cycle progression, viral infection, apoptosis, transcription, and regulating circadian rhythms.[15][16]
CSNK2A1 contains highly conserved functional domains, including a glycine-rich loop, which is a critical structure common to kinases that has roles in substrate recognition, enzyme catalysis, and nucleotide binding. While both alpha isoforms (α, α') are present in major brain regions, there is a predominance of CK2α over CK2α' in the mammalian brain at an approximate ratio of CK2α:CK2α' as 8:1.[17]
Clinical Significance
Mutations in CSNK2A1 are causative for Okur-Chung Neurodevelopmental Syndrome (OCNDS).[18] There are "hot spots" where mutations are more likely to occur, with ~33% of individuals with OCNDS harboring the same genetic change: p. Lys198R[19]
Interactions
More than one-third of CK2 protein substrates are implicated in gene expression and protein synthesis as either transcription factors, translational elements, or effectors of DNA/RNA structure.[20] Casein kinase 2, alpha 1 has been shown to interact with: