title: Structure of a yeast spliceosome at 3.6-angstrom resolution.
abstract: Splicing of precursor messenger RNA (pre-mRNA) in yeast is executed by the spliceosome, which consists of five small nuclear ribonucleoproteins (snRNPs), NTC (nineteen complex), NTC-related proteins (NTR), and a number of associated enzymes and cofactors. Here, we report the three-dimensional structure of a Schizosaccharomyces pombe spliceosome at 3.6-angstrom resolution, revealed by means of single-particle cryogenic electron microscopy. This spliceosome contains U2 and U5 snRNPs, NTC, NTR, U6 small nuclear RNA, and an RNA intron lariat. The atomic model includes 10,574 amino acids from 37 proteins and four RNA molecules, with a combined molecular mass of approximately 1.3 megadaltons. Spp42 (Prp8 in Saccharomyces cerevisiae), the key protein component of the U5 snRNP, forms a central scaffold and anchors the catalytic center. Both the morphology and the placement of protein components appear to have evolved to facilitate the dynamic process of pre-mRNA splicing. Our near-atomic-resolution structure of a central spliceosome provides a molecular framework for mechanistic understanding of pre-mRNA splicing.
authors: Ministry of Education Key Laboratory of Protein Science, Tsinghua-Peking Joint Center for Life Sciences, Center for Structural Biology, School of Life Sciences, Tsinghua University, Beijing 100084, China.
authors: Chuangye
authors: C
authors: Yan
authors: Ministry of Education Key Laboratory of Protein Science, Tsinghua-Peking Joint Center for Life Sciences, Center for Structural Biology, School of Life Sciences, Tsinghua University, Beijing 100084, China.
authors: Jing
authors: J
authors: Hang
authors: Ministry of Education Key Laboratory of Protein Science, Tsinghua-Peking Joint Center for Life Sciences, Center for Structural Biology, School of Life Sciences, Tsinghua University, Beijing 100084, China.
authors: Ruixue
authors: R
authors: Wan
authors: National Center for Protein Science Shanghai, Institute of Biochemistry and Cell Biology, Shanghai Institutes of Biological Sciences, Chinese Academy of Sciences, Shanghai 200031, China.
authors: Min
authors: M
authors: Huang
authors: National Center for Protein Science Shanghai, Institute of Biochemistry and Cell Biology, Shanghai Institutes of Biological Sciences, Chinese Academy of Sciences, Shanghai 200031, China.
authors: Catherine C L
authors: CC
authors: Wong
authors: Ministry of Education Key Laboratory of Protein Science, Tsinghua-Peking Joint Center for Life Sciences, Center for Structural Biology, School of Life Sciences, Tsinghua University, Beijing 100084, China.
authors: Yigong
authors: Y
authors: Shi
mesh_terms: D020134:Catalytic Domain; D020285:Cryoelectron Microscopy; D008958:Models, Molecular; D017433:Protein Structure, Secondary; D012342:RNA, Small Nuclear / Q000737:chemistry; D012097:Repressor Proteins / Q000737:chemistry; D017415:Ribonucleoprotein, U5 Small Nuclear / Q000737:chemistry; D012568:Schizosaccharomyces / Q000648:ultrastructure*; D029702:Schizosaccharomyces pombe Proteins / Q000737:chemistry; D017381:Spliceosomes / Q000737:chemistry* / Q000648:ultrastructure*
chemical_list: D012342:RNA, Small Nuclear; D012097:Repressor Proteins; D017415:Ribonucleoprotein, U5 Small Nuclear; D029702:Schizosaccharomyces pombe Proteins; C401304:Spp42 protein, S pombe; C405486:U6 small nuclear RNA