Kinetochore Associated Protein 2 (KNTC2)

HEC is one of several proteins involved in spindle checkpoint signaling. This surveillance mechanism assures correct segregation of chromosomes during cell division by detecting unaligned chromosomes and causing prometaphase arrest until the proper bipolar attachment of chromosomes is achieved.

The deduced 642-amino acid protein has a calculated molecular mass of 72 kD. HEC has a series of typical leucine heptad repeats that covers the last two-thirds of its sequence. Northern blot analysis revealed a 2.3-kb mRNA in all cell lines tested. Tumor cell lines expressed HEC more abundantly than did normal tissues and untransformed cells. Northern blot analysis of synchronized CV1 monkey kidney cells showed highest expression during S and M phases.