title: Rfc5p regulates alternate RFC complex functions in sister chromatid pairing reactions in budding yeast.
abstract: Sister chromatid pairing reactions, termed cohesion establishment, occur during S-phase and appear to be regulated by Replication Factor C (RFC) complexes. For instance, RFCs that contain Ctf18p exhibit pro-establishment activities while those that contain Elg1p exhibit anti-establishment activities. It remains unknown whether Ctf18p-RFC and Elg1p-RFC functions are simply opposing or instead reveal complicated and non-parallel regulatory mechanisms. To better understand the nature of these novel pathways, we analyzed the small RFC subunit Rfc5p that is common to both Ctf18p-RFC and Elg1p-RFC. Despite this commonality, the data show that diminished Rfc5p function rescues ctf7/eco1 mutant cell phenotypes, revealing that Rfc5p promotes anti-establishment activities. This rescue is specific to establishment pathways in that rfc5-1 greatly accentuates growth defects when expressed in scc2 (deposition), mcd1/scc1 or smc3 (cohesion maintenance) mutated cells. Our results reveal for the first time a role for small RFC subunits in directing RFC complex functions-in this case towards anti-establishment pathways. We further report that Pds5p exhibits both establishment and anti-establishment functions in cohesion. This duality suggests that categorizations of establishment and anti-establishment activities require further examination.
authors.affiliation: Dept. of Biological Sciences, Lehigh University, Bethlehem, PA, USA.
authors.forename: Marie E
authors.initials: ME
authors.lastname: Maradeo
authors.forename: Anisha
authors.initials: A
authors.lastname: Garg
authors.forename: Robert V
authors.initials: RV
authors.lastname: Skibbens
mesh_terms: D000123:Acetyltransferases / Q000235:genetics / Q000378:metabolism; D018797:Cell Cycle Proteins / Q000235:genetics / Q000378:metabolism; D002842:Chromatids / Q000378:metabolism*; D002868:Chromosomal Proteins, Non-Histone / Q000235:genetics / Q000378:metabolism; D018840:HSP70 Heat-Shock Proteins / Q000235:genetics / Q000378:metabolism; D024101:Mitochondrial Proteins / Q000235:genetics / Q000378:metabolism; D009687:Nuclear Proteins / Q000235:genetics / Q000378:metabolism; D021122:Protein Subunits / Q000235:genetics / Q000378:metabolism / Q000502:physiology; D051818:Replication Protein C / Q000235:genetics / Q000378:metabolism* / Q000502:physiology; D016196:S Phase; D012441:Saccharomyces cerevisiae / Q000378:metabolism*; D029701:Saccharomyces cerevisiae Proteins / Q000235:genetics / Q000378:metabolism*
chemical_list: D018797:Cell Cycle Proteins; D002868:Chromosomal Proteins, Non-Histone; D018840:HSP70 Heat-Shock Proteins; C490529:MCD1 protein, S cerevisiae; D024101:Mitochondrial Proteins; D009687:Nuclear Proteins; D021122:Protein Subunits; C120372:SMC3 protein, S cerevisiae; C115913:SSQ1 protein, S cerevisiae; D029701:Saccharomyces cerevisiae Proteins; D000123:Acetyltransferases; C118076:ECO1 protein, S cerevisiae; D051818:Replication Protein C