Induction of Secretory Pathway Components in Yeast Is Associated with Increased Stability of Their mRNA

• Published in: The Journal of cell biology Vol. 156; no. 6; pp. 993 - 1001
• Main Authors: Hyde, Maureen, Block-Alper, Laura, Felix, Jahaira, Webster, Paul, Meyer, David I.
• Format: Journal Article
• Language: English
• Published: United States Rockefeller University Press 18.03.2002; The Rockefeller University Press
• Subjects: Bodily Secretions - physiology; Cell growth; Cells; Cells, Cultured; Cellular biology; Endoplasmic Reticulum - metabolism; Endoplasmic Reticulum - ultrastructure; ErbB Receptors - metabolism; Fungal Proteins - genetics; Fungal Proteins - metabolism; Gene Expression Regulation, Fungal - physiology; Genes; HSP70 Heat-Shock Proteins - genetics; HSP70 Heat-Shock Proteins - metabolism; Intracellular Membranes - metabolism; Intracellular Membranes - ultrastructure; Lipids - biosynthesis; Membrane Glycoproteins - genetics; Membrane Glycoproteins - metabolism; Membranes; Messenger RNA; Microscopy, Electron; P branes; p180 protein; Polyribosomes; Protein Folding; Protein Serine-Threonine Kinases; Proteins; Receptor, ErbB-4; Receptors, Cytoplasmic and Nuclear - metabolism; Ribonucleic acid; Ribosomes; RNA; RNA, Messenger - metabolism; Saccharomyces cerevisiae; Saccharomyces cerevisiae - metabolism; Saccharomyces cerevisiae - ultrastructure; Saccharomyces cerevisiae Proteins; Secretory pathway; Transcription, Genetic - physiology; Yeast; Yeasts
• ISSN: 0021-9525; 1540-8140
• DOI: 10.1083/jcb.200112008

The overexpression of certain membrane proteins is accompanied by a striking proliferation of intracellular membranes. One of the best characterized inducers of membrane proliferation is the 180-kD mammalian ribosome receptor (p180), whose expression in yeast results in increases in levels of mRNAs encoding proteins that function in the secretory pathway, and an elevation in the cell's ability to secrete proteins. In this study we demonstrate that neither the unfolded protein response nor increased transcription accounts for membrane proliferation or the observed increase in secretory pathway mRNAs. Rather, p180-induced up-regulation of certain secretory pathway transcripts is due to a p180-mediated increase in the longevity of these mRNA species, as determined by measurements of transcriptional activity and specific mRNA turnover. Moreover, we show that the longevity of mRNA in general is substantially promoted through the process of its targeting to the membrane of the endoplasmic reticulum. With respect to the terminal differentiation of secretory tissues, results from this model system provide insights into how the expression of a single protein, p180, could result in substantial morphological and functional changes.