Spindle assembly checkpoint proteins are positioned close to core microtubule attachment sites at kinetochores

• DOI: 10.1083/jcb.201304197
• Publication Date: 2013-08-27T03:41:22Z
• Authors: Dileep Varma; Xiaohu Wan; Dhanya Cheerambathur; Reto Gassmann; Aussie Suzuki; Josh Lawrimore; Arshad Desai; E.D. Salmon
• Keywords: Mad2; Spindle checkpoint

Spindle assembly checkpoint proteins have been thought to reside in the peripheral corona region of kinetochore, distal microtubule attachment sites at outer plate. However, recent biochemical evidence indicates that are closely linked core kinetochore site comprised Knl1–Mis12–Ndc80 (KMN) complexes/KMN network. In this paper, we show Knl1–Zwint1 complex is required recruit Rod–Zwilch–Zw10 (RZZ) and Mad1–Mad2 complexes kinetochore. Consistent with this, nanometer-scale mapping RZZ, Mad1–Mad2, C terminus dynein recruitment factor Spindly juxtaposed KMN network metaphase cells when their dissociation blocked active. contrast, N ∼75 nm outside calponin homology domain Ndc80 complex. These results reveal how integrated within substructure will aid understanding coordination signaling during chromosome segregation.