Format

Send to

Choose Destination
EMBO J. 2000 Sep 1;19(17):4723-33.

Multiple portions of poly(A)-binding protein stimulate translation in vivo.

Author information

1
Department of Biochemistry, 433 Babcock Drive, University of Wisconsin-Madison, Madison, WI 53706, USA.

Abstract

Translational stimulation of mRNAs during early development is often accompanied by increases in poly(A) tail length. Poly(A)-binding protein (PAB) is an evolutionarily conserved protein that binds to the poly(A) tails of eukaryotic mRNAs. We examined PAB's role in living cells, using both Xenopus laevis oocytes and Saccharomyces cerevisiae, by tethering it to the 3'-untranslated region of reporter mRNAs. Tethered PAB stimulates translation in vivo. Neither a poly(A) tail nor PAB's poly(A)-binding activity is required. Multiple domains of PAB act redundantly in oocytes to stimulate translation: the interaction of RNA recognition motifs (RRMs) 1 and 2 with eukaryotic initiation factor-4G correlates with translational stimulation. Interaction with Paip-1 is insufficient for stimulation. RRMs 3 and 4 also stimulate, but bind neither factor. The regions of tethered PAB required in yeast to stimulate translation and stabilize mRNAs differ, implying that the two functions are distinct. Our results establish that oocytes contain the machinery necessary to support PAB-mediated translation and suggest that PAB may be an important participant in translational regulation during early development.

PMID:
10970864
PMCID:
PMC302064
DOI:
10.1093/emboj/19.17.4723
[Indexed for MEDLINE]
Free PMC Article

Supplemental Content

Full text links

Icon for HighWire Icon for PubMed Central
Loading ...
Support Center