title: Introns regulate the production of ribosomal proteins by modulating splicing of duplicated ribosomal protein genes.
abstract: Most budding yeast introns exist in the many duplicated ribosomal protein genes (RPGs) and it has been posited that they remain there to modulate the expression of RPGs and cell growth in response to stress. However, the mechanism by which introns regulate the expression of RPGs and their impact on the synthesis of ribosomal proteins remain unclear. In this study, we show that introns determine the ratio of ribosomal protein isoforms through asymmetric paralog-specific regulation of splicing. Exchanging the introns and 3' untranslated regions of the duplicated RPS9 genes altered the splicing efficiency and changed the ratio of the ribosomal protein isoforms. Mutational analysis of the RPS9 genes indicated that splicing is regulated by variations in the intron structure and the 3' untranslated region. Together these data suggest that preferential splicing of duplicated RPGs provides a means for adjusting the ratio of different ribosomal protein isoforms, while maintaining the overall expression level of each ribosomal protein.
authors.affiliation: Université de Sherbrooke Centre of Excellence in RNA Biology, Département de microbiologie et d'infectiologie, Faculté de médecine et des sciences de la santé, Université de Sherbrooke, Sherbrooke, Québec J1E 4K8, Canada.
authors.forename: Cyrielle
authors.initials: C
authors.lastname: Petibon
authors.affiliation: Université de Sherbrooke Centre of Excellence in RNA Biology, Département de microbiologie et d'infectiologie, Faculté de médecine et des sciences de la santé, Université de Sherbrooke, Sherbrooke, Québec J1E 4K8, Canada.
authors.forename: Julie
authors.initials: J
authors.lastname: Parenteau
authors.affiliation: Université de Sherbrooke Centre of Excellence in RNA Biology, Département de microbiologie et d'infectiologie, Faculté de médecine et des sciences de la santé, Université de Sherbrooke, Sherbrooke, Québec J1E 4K8, Canada.
authors.forename: Mathieu
authors.initials: M
authors.lastname: Catala
authors.affiliation: Université de Sherbrooke Centre of Excellence in RNA Biology, Département de microbiologie et d'infectiologie, Faculté de médecine et des sciences de la santé, Université de Sherbrooke, Sherbrooke, Québec J1E 4K8, Canada sherif.abou.elela@usherbrooke.ca.
authors.forename: Sherif Abou
authors.initials: SA
authors.lastname: Elela
mesh_terms: D020413:3' Untranslated Regions; D015966:Gene Expression Regulation, Fungal; D020131:Genes, Duplicate; D007438:Introns; D014176:Protein Biosynthesis; D020033:Protein Isoforms / Q000096:biosynthesis / Q000235:genetics; D012326:RNA Splicing; D000091243:Ribosomal Protein S9; D012269:Ribosomal Proteins / Q000096:biosynthesis / Q000235:genetics* / Q000378:metabolism; D029701:Saccharomyces cerevisiae Proteins / Q000235:genetics / Q000378:metabolism
chemical_list: D020413:3' Untranslated Regions; D020033:Protein Isoforms; D000091243:Ribosomal Protein S9; D012269:Ribosomal Proteins; D029701:Saccharomyces cerevisiae Proteins