Cloning and expression of eukaryotic initiation factor 4B cDNA: sequence determination identifies a common RNA recognition motif.

Milburn, Susan C.; Hershey, John W.B.; Davies, Monique V.; Kelleher, Kerry; Kaufman, Randal J.

doi:10.1002/j.1460-2075.1990.tb07466.x

Cited by 124 publications

(99 citation statements)

References 66 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…yeIF4B binds directly to the 40S subunit and ssRNA Previous studies suggested that mammalian eIF4B binds to ssRNA and 18S rRNA (Milburn et al 1990;Hughes et al 1993;Naranda et al 1994;Methot et al 1996a,b), and that yeIF4B also binds ssRNA (Altmann et al 1995;Niederberger et al 1998). We developed assays to quantify binding of purified yeIF4B to ssRNA and purified ribosomal subunits in vitro.…”

Section: Resultsmentioning

confidence: 99%

Yeast eIF4B binds to the head of the 40S ribosomal subunit and promotes mRNA recruitment through its N-terminal and internal repeat domains

Walker

Zhou

Mitchell

et al. 2012

RNA

154

View full text Add to dashboard Cite

Eukaryotic translation initiation factor (eIF)4B stimulates recruitment of mRNA to the 43S ribosomal pre-initiation complex (PIC). Yeast eIF4B (yeIF4B), shown previously to bind single-stranded (ss) RNA, consists of an N-terminal domain (NTD), predicted to be unstructured in solution; an RNA-recognition motif (RRM); an unusual domain comprised of seven imperfect repeats of 26 amino acids; and a C-terminal domain. Although the mechanism of yeIF4B action has remained obscure, most models have suggested central roles for its RRM and ssRNA-binding activity. We have dissected the functions of yeIF4B's domains and show that the RRM and its ssRNA-binding activity are dispensable in vitro and in vivo. Instead, our data indicate that the 7-repeats and NTD are the most critical domains, which mediate binding of yeIF4B to the head of the 40S ribosomal subunit via interaction with Rps20. This interaction induces structural changes in the ribosome's mRNA entry channel that could facilitate mRNA loading. We also show that yeIF4B strongly promotes productive interaction of eIF4A with the 43S•mRNA PIC in a manner required for efficient mRNA recruitment.

show abstract

Section: Resultsmentioning

confidence: 99%

Yeast eIF4B binds to the head of the 40S ribosomal subunit and promotes mRNA recruitment through its N-terminal and internal repeat domains

Walker

Zhou

Mitchell

et al. 2012

RNA

154

View full text Add to dashboard Cite

show abstract

“…Retarded migration of a number of proteins with unevenly distributed charged residues has been observed, e.g. hnRNP proteins Cl/C2 and initiation factor eIF-4B [4,7].…”

Section: Resultsmentioning

confidence: 99%

Cloning and sequence analysis of a human type A/B hnRNP protein

1991

View full text Add to dashboard Cite

A cDNA encoding a 284 residue long type A/B hnRNP protein has been cloned. This protein, previously rcfcrred to as type C [(1987) J. Biol. Chcm. 262, 17126-171371, is an RNA unwinding protein from HeLa 40s hnRNP with a high affinity for G-followed by U-rich sequences. The N-terminal part of the protein contains two consensus RNA binding domains prcscnt in a number of other RNA binding proteins, The C-terminal part is glycine-rich and contains a potential ATP/GTP binding loop. The distribution of charged amino acids is highly uneven and there are multiple potential phosphorylation sites.hnRNP protein; RNA binding motif; Domain structure

show abstract

“…Other than both containing a well-defined RNA recognition motif (RRM) (Milburn et al 1990;Richter-Cook et al 1998), 4B and 4H bear very little sequence similarity to one another. 4B's RRM has been proposed to interact with 18S rRNA and thereby promote association of the small ribosomal subunit with capbound translation initiation factors (Methot et al 1996a).…”

Section: Discussionmentioning

confidence: 99%

Interactions between eIF4AI and its accessory factors eIF4B and eIF4H

Rozovsky¹,

Butterworth²,

Moore³

2008

RNA

View full text Add to dashboard Cite

Ribonucleoprotein complexes (RNP) remodeling by DEAD-box proteins is required at all stages of cellular RNA metabolism. These proteins are composed of a core helicase domain lacking sequence specificity; flanking protein sequences or accessory proteins target and affect the core's activity. Here we examined the interaction of eukaryotic initiation factor 4AI (eIF4AI), the founding member of the DEAD-box family, with two accessory factors, eIF4B and eIF4H. We find that eIF4AI forms a stable complex with RNA in the presence of AMPPNP and that eIF4B or eIF4H can add to this complex, also dependent on AMPPNP. For both accessory factors, the minimal stable complex with eIF4AI appears to have 1:1 protein stoichiometry. However, because eIF4B and eIF4H share a common binding site on eIF4AI, their interactions are mutually exclusive. The eIF4AI:eIF4B and eIF4AI:eIF4H complexes have the same RNase resistant footprint as does eIF4AI alone (9-10 nucleotides [nt]). In contrast, in a selective RNA binding experiment, eIF4AI in complex with either eIF4B or eIF4H preferentially bound RNAs much longer than those bound by eIF4AI alone (30-33 versus 17 nt, respectively). The differences between the RNase resistant footprints and the preferred RNA binding site sizes are discussed, and a model is proposed in which eIF4B and eIF4H contribute to RNA affinity of the complex through weak interactions not detectable in structural assays. Our findings mirror and expand on recent biochemical and structural data regarding the interaction of eIF4AI's close relative eIF4AIII with its accessory protein MLN51.

show abstract

Cloning and expression of eukaryotic initiation factor 4B cDNA: sequence determination identifies a common RNA recognition motif.

Cited by 124 publications

References 66 publications

Yeast eIF4B binds to the head of the 40S ribosomal subunit and promotes mRNA recruitment through its N-terminal and internal repeat domains

Yeast eIF4B binds to the head of the 40S ribosomal subunit and promotes mRNA recruitment through its N-terminal and internal repeat domains

Cloning and sequence analysis of a human type A/B hnRNP protein

Interactions between eIF4AI and its accessory factors eIF4B and eIF4H

Contact Info

Product

Resources

About