Structural highlights
Function
[PABP1_HUMAN] Binds the poly(A) tail of mRNA. May be involved in cytoplasmic regulatory processes of mRNA metabolism such as pre-mRNA splicing. Its function in translational initiation regulation can either be enhanced by PAIP1 or repressed by PAIP2. Can probably bind to cytoplasmic RNA sequences other than poly(A) in vivo. Involved in translationally coupled mRNA turnover. Implicated with other RNA-binding proteins in the cytoplasmic deadenylation/translational and decay interplay of the FOS mRNA mediated by the major coding-region determinant of instability (mCRD) domain. Involved in regulation of nonsense-mediated decay (NMD) of mRNAs containing premature stop codons; for the recognition of premature termination codons (PTC) and initiation of NMD a competitive interaction between UPF1 and PABPC1 with the ribosome-bound release factors is proposed.[1] [2] [ERF3A_HUMAN] Involved in translation termination in response to the termination codons UAA, UAG and UGA. Stimulates the activity of ERF1. Involved in regulation of mammalian cell growth. Component of the transient SURF complex which recruits UPF1 to stalled ribosomes in the context of nonsense-mediated decay (NMD) of mRNAs containing premature stop codons.
Evolutionary Conservation
Check, as determined by ConSurfDB. You may read the explanation of the method and the full data available from ConSurf.
Publication Abstract from PubMed
PABPC1 (cytosolic poly(A)-binding protein 1) is an RNA-binding protein that binds to the poly(A) tail of mRNAs to promote translation and mRNA turnover. In addition to RNA-binding domains, PABPC1 contains a unique protein-protein interaction domain, MLLE (also known as PABC) that binds regulatory proteins and translation factors that contain a conserved 12 amino acid peptide motif termed PAM2. Eukaryotic Release Factor 3 (eRF3/GSPT1) contains two overlapping PAM2 sequences, which are required for its activity. Here, we determined the crystal structures of the MLLE domain from PABPC1 in complex with the two PAM2 regions of eRF3. The structures reveal a mechanism of cooperativity between the two PAM2 sites that increases the binding affinity but prevents the binding of more than one molecule of eRF3 to PABPC1. Relative to previous structures, the high-resolution crystal structures force a re-evaluation of the PAM2 motif and improve our understanding of the molecular basis of MLLE peptide recognition.
Molecular basis of eRF3 recognition by the MLLE domain of poly(A)-binding protein.,Kozlov G, Gehring K PLoS One. 2010 Apr 14;5(4):e10169. PMID:20418951[3]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
References
- ↑ Grosset C, Chen CY, Xu N, Sonenberg N, Jacquemin-Sablon H, Shyu AB. A mechanism for translationally coupled mRNA turnover: interaction between the poly(A) tail and a c-fos RNA coding determinant via a protein complex. Cell. 2000 Sep 29;103(1):29-40. PMID:11051545
- ↑ Singh G, Rebbapragada I, Lykke-Andersen J. A competition between stimulators and antagonists of Upf complex recruitment governs human nonsense-mediated mRNA decay. PLoS Biol. 2008 Apr 29;6(4):e111. doi: 10.1371/journal.pbio.0060111. PMID:18447585 doi:10.1371/journal.pbio.0060111
- ↑ Kozlov G, Gehring K. Molecular basis of eRF3 recognition by the MLLE domain of poly(A)-binding protein. PLoS One. 2010 Apr 14;5(4):e10169. PMID:20418951 doi:10.1371/journal.pone.0010169
