1I81

CRYSTAL STRUCTURE OF A HEPTAMERIC LSM PROTEIN FROM METHANOBACTERIUM THERMOAUTOTROPHICUM

Summary for 1I81

• Entry DOI: 10.2210/pdb1i81/pdb
• Related: 1B34 1D3B
• Descriptor: PUTATIVE SNRNP SM-LIKE PROTEIN (2 entities in total)
• Functional Keywords: curved anti-parallel beta sheet, structural genomics
• Biological source: Methanothermobacter thermautotrophicus
• Total number of polymer chains: 7
• Total formula weight: 64291.07

Authors

Collins, B.M.,Harrop, S.J.,Kornfeld, G.D.,Dawes, I.W.,Curmi, P.M.G.,Mabbutt, B.C. (deposition date: 2001-03-12, release date: 2001-03-28, Last modification date: 2023-08-09)

Primary citation

Collins, B.M.,Harrop, S.J.,Kornfeld, G.D.,Dawes, I.W.,Curmi, P.M.,Mabbutt, B.C.
Crystal structure of a heptameric Sm-like protein complex from archaea: implications for the structure and evolution of snRNPs.
J.Mol.Biol., 309:915-923, 2001

PubMed Abstract: The Sm/Lsm proteins associate with small nuclear RNA to form the core of small nuclear ribonucleoproteins, required for processes as diverse as pre-mRNA splicing, mRNA degradation and telomere formation. The Lsm proteins from archaea are likely to represent the ancestral Sm/Lsm domain. Here, we present the crystal structure of the Lsm alpha protein from the thermophilic archaeon Methanobacterium thermoautotrophicum at 2.0 A resolution. The Lsm alpha protein crystallizes as a heptameric ring comprised of seven identical subunits interacting via beta-strand pairing and hydrophobic interactions. The heptamer can be viewed as a propeller-like structure in which each blade consists of a seven-stranded antiparallel beta-sheet formed from neighbouring subunits. There are seven slots on the inner surface of the heptamer ring, each of which is lined by Asp, Asn and Arg residues that are highly conserved in the Sm/Lsm sequences. These conserved slots are likely to form the RNA-binding site. In archaea, the gene encoding Lsm alpha is located next to the L37e ribosomal protein gene in a putative operon, suggesting a role for the Lsm alpha complex in ribosome function or biogenesis.

PubMed: 11399068
DOI: 10.1006/jmbi.2001.4693

Experimental method

X-RAY DIFFRACTION (2 Å)