title: The yeast eukaryotic translation initiation factor 2B translation initiation complex interacts with the fatty acid synthesis enzyme YBR159W and endoplasmic reticulum membranes.
abstract: Using affinity purifications coupled with mass spectrometry and yeast two-hybrid assays, we show the Saccharomyces cerevisiae translation initiation factor complex eukaryotic translation initiation factor 2B (eIF2B) and the very-long-chain fatty acid (VLCFA) synthesis keto-reductase enzyme YBR159W physically interact. The data show that the interaction is specifically between YBR159W and eIF2B and not between other members of the translation initiation or VLCFA pathways. A ybr159wΔ null strain has a slow-growth phenotype and a reduced translation rate but a normal GCN4 response to amino acid starvation. Although YBR159W localizes to the endoplasmic reticulum membrane, subcellular fractionation experiments show that a fraction of eIF2B cofractionates with lipid membranes in a YBR159W-independent manner. We show that a ybr159wΔ yeast strain and other strains with null mutations in the VLCFA pathway cause eIF2B to appear as numerous foci throughout the cytoplasm.
authors.affiliation: Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, Tennessee, USA.
authors.forename: Christopher M
authors.initials: CM
authors.lastname: Browne
authors.forename: Parimal
authors.initials: P
authors.lastname: Samir
authors.forename: J Scott
authors.initials: JS
authors.lastname: Fites
authors.forename: Seth A
authors.initials: SA
authors.lastname: Villarreal
authors.forename: Andrew J
authors.initials: AJ
authors.lastname: Link
mesh_terms: D015094:3-Hydroxyacyl CoA Dehydrogenases / Q000032:analysis / Q000378:metabolism*; D004721:Endoplasmic Reticulum / Q000378:metabolism; D020717:Eukaryotic Initiation Factor-2B / Q000032:analysis / Q000378:metabolism*; D005227:Fatty Acids / Q000378:metabolism*; D025941:Protein Interaction Mapping; D012441:Saccharomyces cerevisiae / Q000166:cytology / Q000378:metabolism*; D029701:Saccharomyces cerevisiae Proteins / Q000032:analysis / Q000378:metabolism*
chemical_list: D020717:Eukaryotic Initiation Factor-2B; D005227:Fatty Acids; D029701:Saccharomyces cerevisiae Proteins; D015094:3-Hydroxyacyl CoA Dehydrogenases; C579561:YBR159W protein, S cerevisiae