PDBsum entry 6fpp

RNA binding protein

PDB id: 6fpp

Contents

Protein chains

155 a.a.

Ligands

GOL ×4

Metals

_MG

Waters ×215

PDB id:

6fpp

Name:

RNA binding protein

Title:

Structure of s. Pombe mmi1

Structure:

Yth domain-containing protein mmi1. Chain: a, b. Synonym: meiotic mRNA interception protein 1. Engineered: yes

Source:

Schizosaccharomyces pombe (strain 972 / atcc 24843). Organism_taxid: 284812. Gene: mmi1, spcc736.12c. Expressed in: escherichia coli bl21(de3). Expression_system_taxid: 469008. Expression_system_variant: star

Resolution:

1.93Å R-factor: 0.192 R-free: 0.238

Authors:

J.A.W.Stowell,C.H.Hill,M.Yu,J.L.Wagstaff,S.H.Mclaughlin,S.M.V.Freund, L.A.Passmore

Key ref:

J.A.W.Stowell et al. (2018). A low-complexity region in the YTH domain protein Mmi1 enhances RNA binding. J Biol Chem, 293, 9210-9222. PubMed id: 29695507 DOI: 10.1074/jbc.RA118.002291

Date:

11-Feb-18 Release date: 09-May-18

Protein chains

O74958  (MMI1_SCHPO) -  RNA binding exosome specificity factor Mmi1 from Schizosaccharomyces pombe (strain 972 / ATCC 24843)

Seq: 488 a.a.

Struc: 155 a.a.

Enzyme reactions

• Enzyme class: E.C.?

DOI no: 10.1074/jbc.RA118.002291

J Biol Chem 293:9210-9222 (2018)

PubMed id: 29695507

A low-complexity region in the YTH domain protein Mmi1 enhances RNA binding.

J.A.W.Stowell, J.L.Wagstaff, C.H.Hill, M.Yu, S.H.McLaughlin, S.M.V.Freund, L.A.Passmore.

ABSTRACT

Mmi1 is an essential RNA-binding protein in the fission yeast Schizosaccharomyces pombe that eliminates meiotic transcripts during normal vegetative growth. Mmi1 contains a YTH domain that binds specific RNA sequences, targeting mRNAs for degradation. The YTH domain of Mmi1 uses a noncanonical RNA-binding surface that includes contacts outside the conserved fold. Here, we report that an N-terminal extension that is proximal to the YTH domain enhances RNA binding. Using X-ray crystallography, NMR, and biophysical methods, we show that this low-complexity region becomes more ordered upon RNA binding. This enhances the affinity of the interaction of the Mmi1 YTH domain with specific RNAs by reducing the dissociation rate of the Mmi1-RNA complex. We propose that the low-complexity region influences RNA binding indirectly by reducing dynamic motions of the RNA-binding groove and stabilizing a conformation of the YTH domain that binds to RNA with high affinity. Taken together, our work reveals how a low-complexity region proximal to a conserved folded domain can adopt an ordered structure to aid nucleic acid binding.