title: RNA polymerase II subunits link transcription and mRNA decay to translation.
abstract: Little is known about crosstalk between the eukaryotic transcription and translation machineries that operate in different cell compartments. The yeast proteins Rpb4p and Rpb7p represent one such link as they form a heterodimer that shuttles between the nucleus, where it functions in transcription, and the cytoplasm, where it functions in the major mRNA decay pathways. Here we show that the Rpb4/7 heterodimer interacts physically and functionally with components of the translation initiation factor 3 (eIF3), and is required for efficient translation initiation. Efficient translation in the cytoplasm depends on association of Rpb4/7 with RNA polymerase II (Pol II) in the nucleus, leading to a model in which Pol II remotely controls translation. Hence, like in prokaryotes, the eukaryotic translation is coupled to transcription. We propose that Rpb4/7, through its interactions at each step in the mRNA lifecycle, represents a class of factors, "mRNA coordinators," which integrate the various stages of gene expression into a system.
authors.affiliation: Department of Molecular Microbiology, Rappaport Faculty of Medicine, Technion - Israel Institute of Technology, Haifa, 31096, Israel.
authors.forename: Liat
authors.initials: L
authors.lastname: Harel-Sharvit
authors.forename: Naama
authors.initials: N
authors.lastname: Eldad
authors.forename: Gal
authors.initials: G
authors.lastname: Haimovich
authors.forename: Oren
authors.initials: O
authors.lastname: Barkai
authors.forename: Lea
authors.initials: L
authors.lastname: Duek
authors.forename: Mordechai
authors.initials: M
authors.lastname: Choder
mesh_terms: D012321:DNA-Directed RNA Polymerases / Q000378:metabolism; D039621:Eukaryotic Initiation Factor-3 / Q000378:metabolism; D015966:Gene Expression Regulation, Fungal; D009154:Mutation; D014176:Protein Biosynthesis; D012319:RNA Polymerase II / Q000378:metabolism*; D020871:RNA Stability; D012441:Saccharomyces cerevisiae / Q000235:genetics / Q000378:metabolism*; D029701:Saccharomyces cerevisiae Proteins / Q000235:genetics / Q000378:metabolism*; D014158:Transcription, Genetic
chemical_list: D039621:Eukaryotic Initiation Factor-3; D029701:Saccharomyces cerevisiae Proteins; D012319:RNA Polymerase II; C423309:RPB4 protein, S cerevisiae; C470553:RPB7 protein, S cerevisiae; C485634:RPO26 protein, S cerevisiae; D012321:DNA-Directed RNA Polymerases