Evolutionarily Conserved Polyadenosine RNA Binding Protein Nab2 Cooperates with Splicing Machinery To Regulate the Fate of Pre-mRNA

• Type of Material: Article
• Authors: Sharon Soucek, Emory University; Yi Zeng, University of Chicago; Deepti L. Bellur, University of Chicago; Megan Bergkessel, CALTECH; Kevin J. Morris, Emory University; Qiudong Deng, Emory University; Duc Duong, Emory University; Nicholas Seyfried, Emory University; Christine Guthrie, University of California San Francisco; Jonathan P. Staley, University of Chicago; Milo Fasken, Emory University; Anita Corbett, Emory University
• Language: English
• Date: 2016-11-01
• Publisher: American Society for Microbiology
• Publication Version: Final Published Version
• Copyright Statement: © 2016, American Society for Microbiology. All Rights Reserved.
• Final Published Version (URL): http://dx.doi.org/10.1128/MCB.00402-16
• Title of Journal or Parent Work: Molecular and Cellular Biology
• ISSN: 0270-7306
• Volume: 36
• Issue: 21
• Start Page: 2697
• End Page: 2714
• Grant/Funding Information: HHS; National Institute of General Medical Sciences (NIGMS) http://dx.doi.org/10.13039/100000057 GM058728 to .; NIH; National Institute of General Medical Sciences (NIGMS) http://dx.doi.org/10.13039/100000057 GM062264 to .; National Institute of General Medical Sciences (NIGMS) http://dx.doi.org/10.13039/100000057 GM021119 to .; This paper was supported by the following grant(s):
• Keywords: RIBOSOMAL-RNA; BUDDING YEAST; YEAST HOMOLOG; TANDEM ZINC-FINGER; QUALITY-CONTROL; Science & Technology; Cell Biology; POLYADENYLATION SIGNAL; Biochemistry & Molecular Biology; POLY(A) TAIL LENGTH; SACCHAROMYCES-CEREVISIAE; NUCLEAR POLY(A)-BINDING PROTEIN; STRUCTURAL BASIS; Life Sciences & Biomedicine
• Research Categories: Biology, Cell; Chemistry, Biochemistry; Biology, Genetics

Abstract

Numerous RNA binding proteins are deposited onto an mRNA transcript to modulate posttranscriptional processing events ensuring proper mRNA maturation. Defining the interplay between RNA binding proteins that couple mRNA biogenesis events is crucial for understanding how gene expression is regulated. To explore how RNA binding proteins control mRNA processing, we investigated a role for the evolutionarily conserved polyadenosine RNA binding protein, Nab2, in mRNA maturation within the nucleus. This study reveals that nab2 mutant cells accumulate intron-containing pre-mRNA in vivo. We extend this analysis to identify genetic interactions between mutant alleles of nab2 and genes encoding a splicing factor, MUD2, and RNA exosome, RRP6, with in vivo consequences of altered pre-mRNA splicing and poly(A) tail length control. As further evidence linking Nab2 proteins to splicing, an unbiased proteomic analysis of vertebrate Nab2, ZC3H14, identifies physical interactions with numerous components of the spliceosome. We validated the interaction between ZC3H14 and U2AF2/U2AF65. Taking all the findings into consideration, we present a model where Nab2/ZC3H14 interacts with spliceosome components to allow proper coupling of splicing with subsequent mRNA processing steps contributing to a kinetic proofreading step that allows properly processed mRNA to exit the nucleus and escape Rrp6-dependent degradation.