3RK6

Crystal structure of the middle domain of human Paip1

Summary for 3RK6

• Entry DOI: 10.2210/pdb3rk6/pdb
• Descriptor: Polyadenylate-binding protein-interacting protein 1 (2 entities in total)
• Functional Keywords: heat fold, pabp, eif4a, eif3, translation regulator
• Biological source: Homo sapiens (human)
• Cellular location: Cytoplasm : Q9H074
• Total number of polymer chains: 2
• Total formula weight: 52960.38

Authors

Lei, J.,Mesters, J.R.,Hilgenfeld, R. (deposition date: 2011-04-17, release date: 2011-05-18, Last modification date: 2024-02-28)

Primary citation

Lei, J.,Mesters, J.R.,Brunn, A.,Hilgenfeld, R.
Crystal structure of the middle domain of human poly(A)-binding protein-interacting protein 1.
Biochem.Biophys.Res.Commun., 408:680-685, 2011

PubMed Abstract: In eukaryotes, the poly(A)-binding protein (PABP) is one of the important factors for initiation of messenger RNA translation. PABP activity is regulated by the PABP-interacting proteins (Paips), which include Paip1, Paip2A, and Paip2B. Human Paip1 has three different isoforms. Here, we report the crystal structure of the middle domain of Paip1 isoform 2 (Paip1M) as determined by single-wavelength anomalous dispersion phasing. The structure reveals a crescent-shaped domain consisting of 10 α-helices and two antiparallel β-strands forming a β-hairpin. The 10 α-helices are arranged as five HEAT repeats which form a double layer of α helices with a convex and a concave surface. Despite low sequence identity, the overall fold of Paip1M is similar to the middle domain of human eIF4GII and yeast eIF4GI. Moreover, the amino-acid sequence motif and the local structure of eIF4G involved in binding of eIF4A, are conserved in Paip1. The structure reported here is the first of a member of the Paip family, thereby filling a gap in our understanding of initiation of eukaryotic mRNA translation in three dimensions.

PubMed: 21539810
DOI: 10.1016/j.bbrc.2011.04.088

Experimental method

X-RAY DIFFRACTION (2 Å)