title: Eri1: a conserved enzyme at the crossroads of multiple RNA-processing pathways.
abstract: Eri1 is an evolutionarily conserved 3'-5' exoribonuclease that participates in 5.8S rRNA 3' end processing and turnover of replication-dependent histone mRNAs. Over the course of evolution, Eri1 has also been recruited into a variety of conserved and species-specific regulatory small RNA pathways that include endogenous small interfering (si)RNAs and miRNAs. Recent advances in Eri1 biology illustrate the importance of RNA metabolism in epigenetic gene regulation and illuminate common principles and players in RNA biogenesis and turnover. In this review, we highlight Eri1 as a member of a growing class of ribosome- and histone mRNA-associated proteins that have been recruited into divergent RNA metabolic pathways. We summarize recent advances in the understanding of Eri1 function in these pathways and discuss how Eri1 impacts gene expression and physiology in a variety of eukaryotic species. This emerging view highlights the possibility for crosstalk and coregulation of diverse cellular processes regulated by RNA.
authors.affiliation: Department of Microbiology & Immunology, University of California San Francisco, San Francisco, CA 94143, USA; Sandler Asthma Basic Research Center, University of California San Francisco, San Francisco, CA 94143, USA.
authors.forename: Molly F
authors.initials: MF
authors.lastname: Thomas
authors.affiliation: Department of Cell & Tissue Biology, University of California San Francisco, San Francisco, CA 94143, USA.
authors.forename: Noelle D
authors.initials: ND
authors.lastname: L'Etoile
authors.affiliation: Department of Microbiology & Immunology, University of California San Francisco, San Francisco, CA 94143, USA; Sandler Asthma Basic Research Center, University of California San Francisco, San Francisco, CA 94143, USA. Electronic address: mark.ansel@ucsf.edu.
authors.forename: K Mark
authors.initials: KM
authors.lastname: Ansel
mesh_terms: D000818:Animals; D019143:Evolution, Molecular; D005095:Exoribonucleases / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D005786:Gene Expression Regulation; D006657:Histones / Q000235:genetics / Q000378:metabolism; D006801:Humans; D053858:Metabolic Networks and Pathways; D012313:RNA / Q000235:genetics* / Q000378:metabolism*; D012323:RNA Processing, Post-Transcriptional; D012335:RNA, Ribosomal / Q000235:genetics / Q000378:metabolism; D034741:RNA, Small Interfering / Q000235:genetics / Q000378:metabolism; D013379:Substrate Specificity
chemical_list: D006657:Histones; D012335:RNA, Ribosomal; D034741:RNA, Small Interfering; D012313:RNA; D005095:Exoribonucleases
keywords: RNAi; epigenetic regulation; gene expression; histone mRNA; miRNA; rRNA