The yeast hnRNP-like protein Hrp1/Nab4 marks a transcript for nonsense-mediated mRNA decay

Citation
Ci. Gonzalez et al., The yeast hnRNP-like protein Hrp1/Nab4 marks a transcript for nonsense-mediated mRNA decay, MOL CELL, 5(3), 2000, pp. 489-499
Citations number
50
Categorie Soggetti
Cell & Developmental Biology
Journal title
MOLECULAR CELL
ISSN journal
10972765 → ACNP
Volume
5
Issue
3
Year of publication
2000
Pages
489 - 499
Database
ISI
SICI code
1097-2765(200003)5:3<489:TYHPHM>2.0.ZU;2-X
Abstract
The nonsense-mediated mRNA decay (NMD) pathway monitors premature translati on termination and degradess aberrant mRNAs. In yeast, it has been proposed that a surveillance complex searches 3' of a nonsense codon for a downstre am sequence element (DSE) associated with RNA-binding proteins. An interact ion between the complex and the DSE-binding protein(s) triggers NMD. Here w e describe the identification and characterization of the Hrp1/Nab4 protein as a DSE-binding factor that activates NMD. Mutations in HRP1 stabilize no nsense-containing transcripts without affecting the decay of wild-type mRNA s. Hrp1p binds specifically to a DSE-containing RNA and interacts with Upf1 p, a component of the surveillance complex. A mutation in HRP1 that stabili zes nonsense-containing mRNAs abolishes its affinity for the DSE and fails to interact with Upf1p. We present a model describing how Hrp1p marks a tra nscript for rapid decay.