Serine/threonine-protein kinase haspin (Haspin)

Serine/threonine-protein kinase haspin is an atypical, chromosome-associated nuclear kinase that specifically phosphorylates threonine 3 of histone H3 (H3T3) during mitosis and possibly meiosis. Haspin is unusual among kinases due to its distinctive structure: it possesses a highly divergent eukaryotic protein kinase C-terminal domain and unique regulatory features, lacking several canonical motifs found in typical kinases. Haspin plays a critical role in cell division by regulating chromosome condensation and segregation, impacting centromeric cohesion, genome organization, and the mitotic checkpoint. It is expressed predominantly in male germ cells but is also present in various somatic tissues. Inhibition or depletion of haspin disrupts chromosome dynamics and spindle function, which can cause chromosomal segregation errors. Due to its essential roles in cell division and genomic stability, haspin is emerging as a potential target in cancer therapy and other diseases involving aberrant cell proliferation.

Other names

GSG2 (Germ cell-specific gene 2)Haploid germ cell-specific nuclear protein kinaseHistone H3-associated protein kinase

Competitive inhibition of the ATP-binding site of haspin kinase Blockade of H3T3 phosphorylation, interfering with chromatin and spindle assembly checkpoint signaling