Fission yeast Eso1p is required for establishing sister chromatid cohesion during S phase

摘要: Sister chromatid cohesion is essential for cell viability. We have isolated a novel temperature-sensitive lethal mutant named eso1-H17 that displays spindle assembly checkpoint-dependent mitotic delay and abnormal chromosome segregation. At the permissive temperature, shows mild sensitivity to UV irradiation DNA-damaging chemicals. nonpermissive arrested in M phase with viability loss due failure establish sister during S phase. The M-phase arrest phenotype, however, suppressed by inactivation of checkpoint. eso1(+) gene not onset progression DNA replication but has remarkable genetic interactions those genes regulating G(1)-S transition replication. N-terminal two-thirds Eso1p highly homologous polymerase eta budding yeast humans, C-terminal one-third Eco1p (also called Ctf7p), which required establishment cohesion. Deletion analysis determination mutation site reveal function Eco1p/Ctf7p-homologous domain necessary sufficient On other hand, deletion increases irradiation. These results indicate plays dual role region acts cohesion, presumably catalyzes translesion synthesis when template contains lesions block regular