Molecular architecture of the multiprotein splicing factor SF3b.
The splicing factor SF3b is a multiprotein complex essential for the accurate excision of introns from pre-messenger RNA. As an integral component of the U2 small nuclear ribonucleoprotein (snRNP) and the U11/U12 di-snRNP, SF3b is involved in the recognition of the pre-messenger RNA's branch site within the major and minor spliceosomes. We have determined the three-dimensional structure of the human SF3b complex by single-particle electron cryomicroscopy at a resolution of less than 10 angstroms, allowing identification of protein domains with known structural folds. The best fit of a modeled RNA-recognition motif indicates that the protein p14 is located in the central cavity of the complex. The 22 tandem helical repeats of the protein SF3b155 are located in the outer shell of the complex enclosing p14.
Max Planck Institute for Biophysical Chemistry, Am Fassberg 11, 37077 Göttingen, Germany.
Monika M
MM
Golas
Bjoern
B
Sander
Cindy L
CL
Will
Reinhard
R
Lührmann
Holger
H
Stark
D020816:Amino Acid Motifs; D020285:Cryoelectron Microscopy; D006367:HeLa Cells; D006801:Humans; D007091:Image Processing, Computer-Assisted; D046911:Macromolecular Substances; D008958:Models, Molecular; D046912:Multiprotein Complexes; D010750:Phosphoproteins / Q000737:chemistry*; D011487:Protein Conformation; D017510:Protein Folding; D017433:Protein Structure, Secondary; D017434:Protein Structure, Tertiary; D012322:RNA Precursors / Q000737:chemistry / Q000378:metabolism; D012326:RNA Splicing; D000072260:RNA Splicing Factors; D016601:RNA-Binding Proteins; D020449:Repetitive Sequences, Amino Acid; D017413:Ribonucleoprotein, U2 Small Nuclear / Q000737:chemistry*; D017381:Spliceosomes / Q000737:chemistry / Q000378:metabolism
D046911:Macromolecular Substances; D046912:Multiprotein Complexes; D010750:Phosphoproteins; D012322:RNA Precursors; D000072260:RNA Splicing Factors; D016601:RNA-Binding Proteins; D017413:Ribonucleoprotein, U2 Small Nuclear; C112491:SF3B1 protein, human; C486348:SF3B2 protein, human; C486349:SF3B3 protein, human; C486347:SF3B4 protein, human; C491799:Sf3b1 protein, mouse; C437317:U2 small nuclear ribonucleoprotein p14