Previous Article | Next Article ![]()
Molecular and Cellular Biology, August 2001, p. 4900-4908, Vol. 21, No. 15
Laboratory of Biochemistry and Genetics,
National Institute of Diabetes and Digestive and Kidney Diseases,
National Institutes of Health, Bethesda, Maryland
20892-0830,1 and Laboratory of
Eukaryotic Gene Regulation, National Institute of Child Health and
Human Development, National Institutes of Health, Bethesda, Maryland
20892-27162
Received 30 January 2001/Returned for modification 1 March
2001/Accepted 27 April 2001
The 3' poly(A) structure improves translation of a eukaryotic mRNA
by 50-fold in vivo. This enhancement has been suggested to be due to an
interaction of the poly(A) binding protein, Pab1p, with eukaryotic
translation initiation factor 4G (eIF4G). However, we find that
mutation of eIF4G eliminating its interaction with Pab1p does not
diminish the preference for poly(A)+ mRNA in vivo,
indicating another role for poly(A). We show that either the absence of
Fun12p (eIF5B), or a defect in eIF5, proteins involved in 60S ribosomal
subunit joining, specifically reduces the translation of
poly(A)+ mRNA, suggesting that poly(A) may have a role in
promoting the joining step. Deletion of two nonessential putative RNA
helicases (genes SKI2 and SLH1) makes poly(A)
dispensable for translation. However, in the absence of Fun12p,
eliminating Ski2p and Slh1p shows little enhancement of expression of
non-poly(A) mRNA. This suggests that Ski2p and Slh1p block translation
of non-poly(A) mRNA by an effect on Fun12p, possibly by affecting 60S
subunit joining.
0270-7306/01/$04.00+0 DOI: 10.1128/MCB.21.15.4900-4908.2001
Linking the 3' Poly(A) Tail to the Subunit Joining
Step of Translation Initiation: Relations of Pab1p, Eukaryotic
Translation Initiation Factor 5B (Fun12p), and Ski2p-Slh1p
*
Corresponding author. Mailing address: Bldg. 8, Room
225, NIH, 8 Center Dr. MSC 0830, Bethesda, MD 20892-0830. Phone: (301) 496-3452. Fax: (301) 402-0240. E-mail:
wickner{at}helix.nih.gov.
This article has been cited by other articles:
| J. Bacteriol. | J. Virol. | Eukaryot. Cell |
|---|
| Microbiol. Mol. Biol. Rev. | Clin. Vaccine Immunol. | All ASM Journals |
|---|