SBK2/SgK069

SBK2, annotated as SgK069, is a close relative of SBK1 within the atypical NKF1 kinase family and shares the architecture of a catalytic domain coupled to an SH3-binding proline-rich region. Like SBK1, it is expressed at particularly high levels in brain and testis. Functional information on SBK2 is scarce: no validated physiological substrates have been established, and its precise cellular role is under investigation, though its conservation suggests involvement in protein-protein interaction networks similar to those of SBK1. Recombinant SBK2 enables comparative biochemistry within the SBK family and supports efforts to assign substrates and interactions to each paralog.