Fig. 2: The cnd1-K658E condensin mutation impairs the Cnd1-Pmc4 interaction and causes chromosome segregation defects.

a Y2H analysis examining the interaction of wild-type (WT) and mutant Cnd1 with the mediator subunit Pmc4 and the condensin subunit Cnd2. Wild-type or mutant Cnd1 fused to GAL4-BD was co-expressed with Pmc4 or Cnd2 fused to GAL4-AD. The control plate (SD-Trp-Leu) was used to maintain the GAL4-BD and GAL4-AD plasmids, whereas the +Aur plate (SD-Trp-Lue-His-Ade containing 125 ng/ml aureobasidin A) was used to assess Y2H interactions. b Co-IP analysis investigating the interaction of wild-type and mutant Cnd1-Myc with Pmc4-Pk. Three independent experiments showed similar results. c Co-IP analysis showing the interactions of wild-type and mutant Cnd1-Myc with Cnd2-Pk. Three independent experiments showed similar results. d Chromosome segregation defects in the cnd1-K658E mutant strain. Cells carrying the cnd1-WT and cnd1-K658E genes at the endogenous locus were subjected to immunofluorescence analysis to visualize spindle microtubules (mitotic marker) and DAPI-stained DNA. Mitotic cells displaying lagging chromosomes (arrowheads) were quantified. The experiments were conducted in three independent replicates. e Chromosome segregation defects in cells depleted of Pmc4. Cells were cultured in EMM liquid medium containing auxin to deplete the endogenous Pmc4, while exogenous Pmc4 was expressed from a plasmid. The vector control represents cells lacking exogenous Pmc4 expression (Pmc4 depletion). Mitotic defects were analyzed as described in (d). Data in (d, e) are represented as mean ± SD and P-values were calculated by two-sided Student’s t test. Source data for (b-e) are provided as a Source Data file.