title: Genome-Wide Mapping of Uncapped and Cleaved Transcripts Reveals a Role for the Nuclear mRNA Cap-Binding Complex in Cotranslational RNA Decay in Arabidopsis.
abstract: RNA turnover is necessary for controlling proper mRNA levels posttranscriptionally. In general, RNA degradation is via exoribonucleases that degrade RNA either from the 5' end to the 3' end, such as XRN4, or in the opposite direction by the multisubunit exosome complex. Here, we use genome-wide mapping of uncapped and cleaved transcripts to reveal the global landscape of cotranslational mRNA decay in the Arabidopsis thaliana transcriptome. We found that this process leaves a clear three nucleotide periodicity in open reading frames. This pattern of cotranslational degradation is especially evident near the ends of open reading frames, where we observe accumulation of cleavage events focused 16 to 17 nucleotides upstream of the stop codon because of ribosomal pausing during translation termination. Following treatment of Arabidopsis plants with the translation inhibitor cycloheximide, cleavage events accumulate 13 to 14 nucleotides upstream of the start codon where initiating ribosomes have been stalled with these sequences in their P site. Further analysis in xrn4 mutant plants indicates that cotranslational RNA decay is XRN4 dependent. Additionally, studies in plants lacking CAP BINDING PROTEIN80/ABA HYPERSENSITIVE1, the largest subunit of the nuclear mRNA cap binding complex, reveal a role for this protein in cotranslational decay. In total, our results demonstrate the global prevalence and features of cotranslational RNA decay in a plant transcriptome.
authors.affiliation: Department of Biology, University of Pennsylvania, Philadelphia, Pennsylvania 19104.
authors.forename: Xiang
authors.identifier: 0000-0002-5730-8802
authors.initials: X
authors.lastname: Yu
authors.affiliation: Department of Biology, University of Pennsylvania, Philadelphia, Pennsylvania 19104.
authors.forename: Matthew R
authors.initials: MR
authors.lastname: Willmann
authors.affiliation: Department of Biology, University of Pennsylvania, Philadelphia, Pennsylvania 19104.|Biology Graduate Group, University of Pennsylvania, Philadelphia, Pennsylvania 19104.
authors.forename: Stephen J
authors.identifier: 0000-0002-5782-7303
authors.initials: SJ
authors.lastname: Anderson
authors.affiliation: Department of Biology, University of Pennsylvania, Philadelphia, Pennsylvania 19104 bdgregor@sas.upenn.edu.|Biology Graduate Group, University of Pennsylvania, Philadelphia, Pennsylvania 19104.
authors.forename: Brian D
authors.identifier: 0000-0001-7532-0138
authors.initials: BD
authors.lastname: Gregory
mesh_terms: D017360:Arabidopsis / Q000187:drug effects / Q000235:genetics* / Q000378:metabolism*; D029681:Arabidopsis Proteins / Q000235:genetics* / Q000378:metabolism*; D003513:Cycloheximide / Q000494:pharmacology; D005095:Exoribonucleases / Q000235:genetics / Q000378:metabolism; D018506:Gene Expression Regulation, Plant / Q000187:drug effects / Q000235:genetics; D039502:Nuclear Cap-Binding Protein Complex / Q000235:genetics / Q000378:metabolism; D010940:Plant Proteins / Q000235:genetics / Q000378:metabolism; D020871:RNA Stability / Q000235:genetics* / Q000502:physiology; D012333:RNA, Messenger / Q000235:genetics*; D018749:RNA, Plant / Q000235:genetics; D012270:Ribosomes / Q000235:genetics / Q000378:metabolism
chemical_list: D029681:Arabidopsis Proteins; D039502:Nuclear Cap-Binding Protein Complex; D010940:Plant Proteins; D012333:RNA, Messenger; D018749:RNA, Plant; C418137:Xrn1 protein, plant; D003513:Cycloheximide; D005095:Exoribonucleases