title: The polysome-associated proteins Scp160 and Bfr1 prevent P body formation under normal growth conditions.
abstract: Numerous mRNAs are degraded in processing bodies (P bodies) in Saccharomyces cerevisiae. In logarithmically growing cells, only 0-1 P bodies per cell are detectable. However, the number and appearance of P bodies change once the cell encounters stress. Here, we show that the polysome-associated mRNA-binding protein Scp160 interacts with P body components, such as the decapping protein Dcp2 and the scaffold protein Pat1, presumably, on polysomes. Loss of either Scp160 or its interaction partner Bfr1 caused the formation of Dcp2-positive structures. These Dcp2-positive foci contained mRNA, because their formation was inhibited by the presence of cycloheximide. In addition, Scp160 was required for proper P body formation because only a subset of bona fide P body components could assemble into the Dcp2-positive foci in Δscp160 cells. In either Δbfr1 or Δscp160 cells, P body formation was uncoupled from translational attenuation as the polysome profile remained unchanged. Collectively, our data suggest that Bfr1 and Scp160 prevent P body formation under normal growth conditions.
authors.affiliation: Growth & Development, Biozentrum, University of Basel, Klingelbergstrasse 70, 4056 Basel, Switzerland.
authors.forename: Julie
authors.initials: J
authors.lastname: Weidner
authors.forename: Congwei
authors.initials: C
authors.lastname: Wang
authors.forename: Cristina
authors.initials: C
authors.lastname: Prescianotto-Baschong
authors.forename: Alejandro F
authors.initials: AF
authors.lastname: Estrada
authors.forename: Anne
authors.initials: A
authors.lastname: Spang
mesh_terms: D003594:Cytoplasmic Granules / Q000378:metabolism*; D047468:Immunoprecipitation; D008856:Microscopy, Fluorescence; D016253:Microscopy, Immunoelectron; D011132:Polyribosomes / Q000378:metabolism; D020871:RNA Stability; D012333:RNA, Messenger / Q000378:metabolism; D016601:RNA-Binding Proteins / Q000378:metabolism*; D012097:Repressor Proteins / Q000378:metabolism*; D012441:Saccharomyces cerevisiae / Q000378:metabolism*; D029701:Saccharomyces cerevisiae Proteins / Q000378:metabolism*
chemical_list: C089100:BFR1 protein, S cerevisiae; D012333:RNA, Messenger; D016601:RNA-Binding Proteins; D012097:Repressor Proteins; C097262:SCP160 protein, S cerevisiae; D029701:Saccharomyces cerevisiae Proteins
keywords: Endoplasmic reticulum; Processing bodies; Ribonucleotide particles; Saccharomyces cerevisiae; Stress granules; Stress response; Translation; mRNA; mRNA decay; mRNA metabolism; mRNA-binding proteins