Yeast poly(A)-binding protein, Pab1, and PAN, a poly(A) nuclease complex recruited by Pab1, connect mRNA biogenesis to export

Dunn, E. F., Hammell, C. M., Hodge, C. A., Cole, C. N. (2005) Yeast poly(A)-binding protein, Pab1, and PAN, a poly(A) nuclease complex recruited by Pab1, connect mRNA biogenesis to export. Genes and Development, 19 (1). pp. 90-103. ISSN 08909369 (ISSN)

Abstract

In eukaryotic cells, pre-mRNAs undergo extensive processing in the nucleus prior to export. Processing is subject to a quality-control mechanism that retains improperly processed transcripts at or near sites of transcription. A poly(A) tail added by the normal 3′-processing machinery is necessary but not sufficient for export. Retention depends on the exosome. In this study, we identify the poly(A)-binding protein, Pab1, and the poly(A) nuclease, PAN, as important factors that couple 3′ processing to export. Pab1 contains a nonessential leucine-rich nuclear export signal and shuttles between the nucleus and the cytoplasm. It can exit the nucleus either as cargo of exportin 1 or bound to mRNA. Pab1 is essential but several bypass suppressors have been identified. Deletion of PAB1 from these bypass suppressor strains results in exosome-dependent retention at sites of transcription. Retention is also seen in cells lacking PAN, which Pab1 is thought to recruit and which may be responsible for the final step of mRNA biogenesis, trimming of the poly(A) tail to the length found on newly exported mRNAs. The studies presented here suggest that proper loading of Pab1 onto mRNAs and final trimming of the tail allows release from transcription sites and couples pre-mRNA processing to export.

Item Type: Paper
Uncontrolled Keywords: Exportin 1 Gene expression mRNA biogenesis mRNA transport Nuclear export signal Polyadenylation leucine messenger RNA precursor nuclease polyadenylic acid binding protein amino terminal sequence article carboxy terminal sequence gene deletion gene location gene overexpression gene repression genetic identification genetic transcription nonhuman priority journal protein binding signal transduction yeast Active Transport, Cell Nucleus Exoribonucleases Poly(A)-Binding Proteins Protein Sorting Signals Protein Transport RNA Precursors RNA Processing, Post-Transcriptional RNA, Messenger Saccharomyces cerevisiae Saccharomyces cerevisiae Proteins Transcription, Genetic Eukaryota
Subjects: bioinformatics > genomics and proteomics > genetics & nucleic acid processing > DNA, RNA structure, function, modification
bioinformatics > genomics and proteomics > genetics & nucleic acid processing
bioinformatics > genomics and proteomics
bioinformatics > genomics and proteomics > genetics & nucleic acid processing > DNA, RNA structure, function, modification > mRNA dynamics
bioinformatics > genomics and proteomics > genetics & nucleic acid processing > DNA, RNA structure, function, modification > pre-mRNA
organism description > yeast
CSHL Authors:
Communities: CSHL labs > Hammell C. lab
Depositing User: Matt Covey
Date: 2005
Date Deposited: 11 Mar 2013 16:52
Last Modified: 11 Mar 2013 16:52
PMCID: PMC540228
Related URLs:
URI: https://repository.cshl.edu/id/eprint/27744

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