Cooperation of the Dam1 and Ndc80 kinetochore complexes enhances microtubule coupling and is regulated by aurora B

Abstract

The Dam1 complex, regulated by aurora B phosphorylation, confers a more stable microtubule association for the Ndc80 complex at kinetochores (see also related paper by Lampert et al. in this issue).

Regulation of outer kinetochore Ndc80 complex-based microtubule attachments by the central kinetochore Mis12/MIND complex

“…Previous work found that addition of the 10-member outer kinetochore Dam1 complex increased the residence time of Ndc80c 2.6-fold, to 6.4 ± 0.2 s (Fig. 3 A and B) (24). Surprisingly, we found that MIND also dramatically affected the microtubule binding of Ndc80c because the residence time of MIND-GFP/ Ndc80c complexes was 10.4 ± 0.6 s, fourfold longer than that of Ndc80c-GFP (Fig.…”

Long tethers provide high-force coupling of the Dam1 ring to shortening microtubules

“…Although Dam1 and Ndc80 do not interact in solution, Dam1 enhances the binding of Ndc80 to MTs and imparts to it the ability to track with depolymerizing MT ends (26)(27)(28). Interestingly, Ndc80-coated beads supplemented with soluble Dam1 can withstand, on average, only a 4.4-pN load, with the largest measured force of 9 pN (26).…”

A Redundant Function for the N-Terminal Tail of Ndc80 in Kinetochore–Microtubule Interaction in Saccharomyces cerevisiae

“…The Dam1 complex binds MTs in vivo and in vitro and localizes to the KT in a MT-dependent fashion (Li et al 2002). The Dam1 complex, at high concentrations in vitro, oligomerizes into a closed-ring structure that encircles MTs (Miranda et al 2005;Lampert et al 2010;Tien et al 2010). There is an interaction between Dam1 and Ndc80 complexes on MTs in vitro that enhances the ability of Ndc80 to maintain MT attachments (Lampert et al 2010;Tien et al 2010).…”

“…Recombinant Ndc80 complex binds MTs in vitro, and the activity is restricted to the head domains of Nuf2 and Ndc80 (Wei et al 2005;Ciferri et al 2008). Yeast has an additional protein complex, Dam1, composed of 10 proteins, that is also required for KT-MT attachment (Westermann et al 2006;Lampert et al 2010;Tien et al 2010). The Dam1 complex binds MTs in vivo and in vitro and localizes to the KT in a MT-dependent fashion (Li et al 2002).…”

“…Serial 10-fold dilutions of saturated cultures of the indicated genotypes were spotted onto YPD plates containing 15 mg/ml benomyl and grown at 23°for 4 days (D). Tien et al 2010). We constructed double mutants between ndc80-112 and dam1-1 and found that the double mutant was impaired for growth compared to the single mutants when grown at a semipermissive temperature ( Figure 2C).…”