In Saccharomyces cerevisiae Kre28 and Spc105 form a kinetochore microtubule binding complex, which bridges between centromeric heterochromatin and kinetochore MAPs (microtubule associated protein, such as Bim1, Bik1 and SIk19) and motors (Cin8, Kar3) [1]. It may be regulated by sumoylation [2].

1: Roles for the conserved spc105p/kre28p complex in kinetochore-microtubule binding and the spindle assembly checkpoint. Pagliuca C, Draviam VM, Marco E, Sorger PK, De Wulf P; PLoS One. 2009;4:e7640. PMID:19893618

2: The Smc5-Smc6 complex regulates recombination at centromeric regions and affects kinetochore protein sumoylation during normal growth. Yong-Gonzales V, Hang LE, Castellucci F, Branzei D, Zhao X; PLoS One. 2012;7:e51540. PMID:23284708