Structural highlights
Function
IF4F1_YEAST Component of the eIF4F complex, which interacts with the mRNA cap structure and serves as an initial point of assembly for the translation apparatus. Stimulates translation by interaction with polyadenylate-binding protein PAB1, bringing the 5'- and 3'-ends of the mRNA in proximity. The formation of this circular mRNP structure appears to be critical for the synergistic effects of the cap and the poly(A) tail in facilitating translation initiation, recycling of ribosomes, and mRNA stability. TIF4631 is probably essential when TIF4632 is missing.[1] [2] PUB1_YEAST May be associated with hnRNA within the nucleus and remains associated during nucleocytoplasmic mRNA transport, once the proteins are in the cytoplasm, disassembly of PUB1-RNA complexes may occur prior to PAB1 binding and formation of a translationally competent RNP complex. Binds to polyadenylated RNA; prefers to bind poly(rU); binds to T-rich single-stranded DNA.
Publication Abstract from PubMed
Yeast eIF4G1 interacts with RNA binding proteins (RBPs) like Pab1 and Pub1 affecting its function in translation initiation and stress granules formation. We present an NMR and SAXS study of the N-terminal intrinsically disordered region of eIF4G1 (residues 1-249) and its interactions with Pub1, Pab1 and RNA. The conformational ensemble of eIF4G1(1-249) shows an alpha-helix within the BOX3 conserved element and a dynamic network of fuzzy pi-pi and pi-cation interactions involving arginine and aromatic residues. The Pab1 RRM2 domain interacts with eIF4G1 BOX3, the canonical interaction site, but also with BOX2, a conserved element of unknown function to date. The RNA1 region interacts with RNA through a new RNA interaction motif and with the Pub1 RRM3 domain. This later also interacts with eIF4G1 BOX1 modulating its intrinsic self-assembly properties. The description of the biomolecular interactions involving eIF4G1 to the residue detail increases our knowledge about biological processes involving this key translation initiation factor.
eIF4G1 N-terminal intrinsically disordered domain is a multi-docking station for RNA, Pab1, Pub1, and self-assembly.,Chaves-Arquero B, Martinez-Lumbreras S, Sibille N, Camero S, Bernado P, Jimenez MA, Zorrilla S, Perez-Canadillas JM Front Mol Biosci. 2022 Sep 23;9:986121. doi: 10.3389/fmolb.2022.986121. , eCollection 2022. PMID:36213119[3]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
References
- ↑ Tarun SZ Jr, Wells SE, Deardorff JA, Sachs AB. Translation initiation factor eIF4G mediates in vitro poly(A) tail-dependent translation. Proc Natl Acad Sci U S A. 1997 Aug 19;94(17):9046-51. PMID:9256432
- ↑ Otero LJ, Ashe MP, Sachs AB. The yeast poly(A)-binding protein Pab1p stimulates in vitro poly(A)-dependent and cap-dependent translation by distinct mechanisms. EMBO J. 1999 Jun 1;18(11):3153-63. PMID:10357826 doi:http://dx.doi.org/10.1093/emboj/18.11.3153
- ↑ Chaves-Arquero B, Martinez-Lumbreras S, Sibille N, Camero S, Bernado P, Jimenez MA, Zorrilla S, Perez-Canadillas JM. eIF4G1 N-terminal intrinsically disordered domain is a multi-docking station for RNA, Pab1, Pub1, and self-assembly. Front Mol Biosci. 2022 Sep 23;9:986121. doi: 10.3389/fmolb.2022.986121. , eCollection 2022. PMID:36213119 doi:http://dx.doi.org/10.3389/fmolb.2022.986121
