InterPro domain: IPR015275

This domain assumes a secondary structure consisting of eight beta strands and 11 alpha-helices, organised in two lobes. It is predominantly found in actin-fragmin kinase. It is the catalytic domain that mediates the phosphorylation of actin [ 1 ].

An atypical actin-fragmin kinase domain is also found at the N terminus of dual-specificity phosphatases such as propyzamide-hypersensitive 1 (PHS1) [ 2 ].

1. The crystal structure of the Physarum polycephalum actin-fragmin kinase: an atypical protein kinase with a specialized substrate-binding domain. EMBO J. 18, 2923-9
2. The mitogen-activated protein kinase phosphatase PHS1 regulates flowering in Arabidopsis thaliana. Planta 243, 909-23