Which kinase phosphorylates Knl1 to recruit checkpoint proteins at unattached kinetochores?
Assembly of spindle assembly checkpoint proteins at kinetochores requires phosphorylation-dependent creation of docking sites on outer kinetochore scaffold. KNL1, also called Blinkin or Spc105, contains multiple MELT repeats (Met-Glu-Leu-Thr) that become phosphorylated when kinetochore is unattached. The kinase responsible is monopolar spindle 1, abbreviated Mps1, conserved from yeast to humans, dual-specificity kinase that localizes to unattached kinetochores via its TPR domain interacting with Ndc80 complex and calponin homology domains. Mps1 phosphorylation of MELT motifs generates binding
Ref: London & Biggins, Genes Dev 2014, Mps1 and KNL1 Phosphorylation; Vleugel et al., J Cell Biol 2015, MELT Repeats.
