8.Crystal structures of Lsm3, Lsm4 and Lsm5/6/7 from Schizosaccharomyces pombe

编辑: Date:2012/05/17

PLoS One. 2012;7(5):e36768.

Donghui Wu, Shimin Jiang, Matthew W. Bowler, Haiwei Song*

Abstract

Sm-like (Lsm) proteins are ubiquitous and function in many aspects of RNA metabolism, including pre-mRNA splicing,nuclear RNA processing, mRNA decay and miRNA biogenesis. Here three crystal structures including Lsm3, Lsm4 and Lsm5/6/7 sub-complex from S. pombe are reported. These structures show that all the five individual Lsm subunits share aconserved Sm fold, and Lsm3, Lsm4, and Lsm5/6/7 form a heptamer, a trimer and a hexamer within the crystal lattice,respectively. Analytical ultracentrifugation indicates that Lsm3 and Lsm5/6/7 sub-complex exist in solution as a heptamerand a hexamer, respectively while Lsm4 undergoes a dynamic equilibrium between monomer and trimer in solution. RNAbinding assays show that Lsm2/3 and Lsm5/6/7 bind to oligo(U) whereas no RNA binding is observed for Lsm3 and Lsm4.Analysis of the inter-subunit interactions in Lsm5/6/7 reveals the organization order among Lsm5, Lsm6 and Lsm7.

Text link:http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0036768