A tDNA establishes cohesion of a neighboring silent chromatin domain.
DNA replication generates sister chromatid pairs that are bound to one another until anaphase onset. The process, termed sister chromatid cohesion, requires the multisubunit cohesin complex that resides at centromeres and sites where genes converge. At the HMR mating-type locus of budding yeast, cohesin associates with a heterochromatin-like structure known as silent chromatin. In this report, we show that silent chromatin is necessary but not sufficient for cohesion of the replicating locus. A tRNA gene (tDNA) that delimits the silent chromatin domain is also required, as are subunits of the TFIIIB and RSC complexes that bind the gene. Non-tDNA boundary elements do not substitute for tDNAs in cohesion, suggesting that barrier activity is not responsible for the phenomenon. The results reveal an unexpected role for tDNAs and RNA polymerase III-associated proteins in establishment of sister chromatid cohesion.
Dubey
Rudra N
RN
Department of Pharmacology, Robert Wood Johnson Medical School, University of Medicine and Dentistry of New Jersey, Piscataway, New Jersey 08854, USA.
Gartenberg
Marc R
MR
D018797:Cell Cycle Proteins / Q000502:physiology; D002843:Chromatin / Q000502:physiology*; D002868:Chromosomal Proteins, Non-Histone / Q000502:physiology; D004261:DNA Replication; D004268:DNA-Binding Proteins / Q000502:physiology; D020868:Gene Silencing; D049770:Genes, Mating Type, Fungal; D008957:Models, Genetic; D009687:Nuclear Proteins / Q000502:physiology; D012320:RNA Polymerase III / Q000502:physiology*; D012343:RNA, Transfer / Q000235:genetics*; D012441:Saccharomyces cerevisiae; D029701:Saccharomyces cerevisiae Proteins / Q000502:physiology; D035581:Transcription Factor TFIIB / Q000502:physiology; D014157:Transcription Factors / Q000502:physiology; D000097722:Cohesins