Transferases;
Transferring phosphorus-containing groups;
Protein-serine/threonine kinases
BRITE hierarchy

(1) ATP + [protein]-L-serine = ADP + [protein]-O-phospho-L-serine [RN:R13188];
(2) ATP + [protein]-L-threonine = ADP + [protein]-O-phospho-L-threonine [RN:R13189]

R13188 R13189
Reaction

ATP [CPD:C00002];
[protein]-L-serine [CPD:C02189];
[protein]-L-threonine [CPD:C19803]

Requires Mg2+. Peptide array data show a preference for phosphorylation of Thr over Ser and a preference for basic residues in the -5 to -1 positions [1]. CRIK is an animal-specific protein kinase that phosphorylates myosin light chain (cf. EC 2.7.11.18, myosin-light-chain kinase) and is involved in cytokinesis in both mammals and Drosophila. Human CRIK phosphorylates myosin light chain, MYL9/MRLC1 on T19/S20 [2] and GLI2 on S149 [3]. Drosophila CRIK (sticky) interacts with the kinesins Nebbish and Pavarotti, and human CRIK interacts with their orthologs, KIF14 and KIF23/MKLP1 to promote midbody formation during cytokinesis [4]. In Drosophila, CRIK/Sticky catalytic activity was required for this function. Human CRIK is mostly highly expressed in brain, and mutations that alter splicing or kinase activity lead to microcephaly [5, 6], as do knockouts in mouse and rat, and mutations in its interacting partner, the kinesin KIF14 [6].

EC 2.7.11.35 created 2023

1  [PMID:36631611]

2  [PMID:12802051]

3  [PMID:25416949]

4  [PMID:23716662]

5  [PMID:27503289]

6  [PMID:27453578]