6j6h

Cryo-EM structure of the yeast B*-a1 complex at an average resolution of 3.6 angstromCryo-EM structure of the yeast B*-a1 complex at an average resolution of 3.6 angstrom

6j6h, resolution 3.60Å Show:Asymmetric Unit Biological Assembly Structural highlights 6j6h is a 41 chain structure with sequence from Baker's yeast and Saccharomyces cerevisiae s288c. Full crystallographic information is available from OCA. For a guided tour on the structure components use FirstGlance. Ligands: Activity: RING-type E3 ubiquitin transferase, with EC number 2.3.2.27 Experimental data: Check Resources: FirstGlance, OCA, PDBe, RCSB, PDBsum, ProSAT Function [CEF1_YEAST] Involved in pre-mRNA splicing and cell cycle control. Required for the binding of the NTC complex (or PRP19-associated complex) components to the spliceosome to mediate conformational rearrangement or to stabilize the structure of the spliceosome after U4 snRNA dissociation, which leads to spliceosome maturation. Its absence leads to an arrest of the cell cycle, possibly due to the inefficient splicing of TUB1. [MSL1_YEAST] Involved in pre-mRNA splicing. This protein is associated with snRNP U2. It binds stem loop IV of U2 snRNA. [CWC2_YEAST] Involved in the first step of pre-mRNA splicing. Required for cell growth and cell cycle control. Plays a role in the levels of the U1, U4, U5 and U6 snRNAs and the maintenance of the U4/U6 snRNA complex. May provide the link between the "nineteen complex" NTC spliceosome protein complex and the spliceosome through the U6 snRNA. Associates predominantly with U6 snRNAs in assembled active spliceosomes. Binds directly to the internal stem-loop (ISL) domain of the U6 snRNA and to the pre-mRNA intron near the 5' splice site during the activation and catalytic phases of the spliceosome cycle. Binds also to U1, U4, U5 and U6 snRNAs and to pre-mRNAs, in vitro. Is not required for the Prp2-mediated remodeling of the activated spliceosome. [RUXG_YEAST] Involved in pre-mRNA splicing. Binds snRNA U1, U2, U4 and U5 which contain a highly conserved structural motif called the Sm binding site. [SN114_YEAST] Component of the U5 snRNP complex required for pre-mRNA splicing. Binds GTP. [RU2A_YEAST] Involved in pre-mRNA splicing. Associates to U2 snRNA in a MSL1 dependent manner and is required for normal accumulation of U2 snRNA. Required for the spliceosome assembly and the efficient addition of U2 snRNP onto the pre-mRNA. [PRP8_YEAST] Required for pre-spliceosome formation, which is the first step of pre-mRNA splicing. This protein is associated with snRNP U5. Has a role in branch site-3' splice site selection. Associates with the branch site-3' splice 3'-exon region. Also has a role in cell cycle. [SMD3_YEAST] Involved in pre-mRNA splicing. Binds snRNA U1, U2, U4 and U5 which contain a highly conserved structural motif called the Sm binding site. Also binds telomerase RNA and is required for its accumulation. [SN309_YEAST] Involved in pre-mRNA splicing by stabilizing the NTC (or PRP19-associated complex). As a component of the NTC complex, associates to the spliceosome to mediate conformational rearrangement or to stabilize the structure of the spliceosome after U4 snRNA dissociation, which leads to spliceosome maturation. [SYF2_YEAST] Involved in pre-mRNA splicing and cell cycle control. As a component of the NTC complex (or PRP19-associated complex), associates to the spliceosome to mediate conformational rearrangement or to stabilize the structure of the spliceosome after U4 snRNA dissociation, which leads to spliceosome maturation. The cell cycle arrest of SYF2 defective cells may be due to the inefficient splicing of TUB1. [RSMB_YEAST] Involved in pre-mRNA splicing. Binds snRNA U1, U2, U4 and U5 which contain a highly conserved structural motif called the Sm binding site. [RUXF_YEAST] Involved in pre-mRNA splicing. Binds snRNA U1, U2, U4 and U5 which contain a highly conserved structural motif called the Sm binding site. [SMD1_YEAST] Involved in pre-mRNA splicing. Binds snRNA U1, U2, U4 and U5 which contain a highly conserved structural motif called the Sm binding site. Also binds telomerase RNA and is required for its accumulation. [SLT11_YEAST] Involved in pre-mRNA splicing. Facilitates the cooperative formation of U2/U6 helix II in association with stem II in the spliceosome. Binds to RNA. [SMD2_YEAST] Involved in pre-mRNA splicing. Binds snRNA U1, U2, U4 and U5 which contain a highly conserved structural motif called the Sm binding site. [CWC21_YEAST] Involved in pre-mRNA splicing. May function at or prior to the first catalytic step of splicing at the catalytic center of the spliceosome, together with ISY1. May do so by stabilizing the catalytic center or the position of the RNA substrate. [BUD31_YEAST] Involved in pre-mRNA splicing. Important for bud site selection. [CLF1_YEAST] Involved in pre-mRNA splicing and cell cycle progression. Required for the spliceosome assembly by promoting the functional integration of the U4/U6.U5 tri-snRNP particle into the U1-, U2-dependent pre-spliceosome. Also recruits PRP19 to the spliceosome, as a component of the NTC complex (or PRP19-associated complex). The association of the NTC complex to the spliceosome mediates conformational rearrangement or stabilizes the structure of the spliceosome after U4 snRNA dissociation, which leads to spliceosome maturation. Required for initiation of the DNA replication by binding the RNA replication origins, probably through its interaction with the origin recognition complex (ORC). [SYF1_YEAST] Involved in pre-mRNA splicing and cell cycle control. As a component of the NTC complex (or PRP19-associated complex), associates to the spliceosome to mediate conformational rearrangement or to stabilize the structure of the spliceosome after U4 snRNA dissociation, which leads to spliceosome maturation. [PRP17_YEAST] May function in the second step of pre-mRNA splicing. Regulatory protein involved in replication and mitotic spindle formation and/or maintenance. Required for initiation and completion of S-phase and for initiation and completion of DNA replication. Might be required for the maintenance of microtubules. Essential only at elevated temperatures. [ISY1_YEAST] Involved in pre-mRNA splicing and cell cycle control. As a component of the NTC complex (or PRP19-associated complex), associates to the spliceosome to mediate conformational rearrangement or to stabilize the structure of the spliceosome after U4 snRNA dissociation, which leads to spliceosome maturation. The cell cycle arrest of SYF2 defective cells may be due to the inefficient splicing of TUB1. Also involved in DNA repair. [CWC15_YEAST] Involved in pre-mRNA splicing. [PRP46_YEAST] Involved in pre-mRNA splicing. May also be required for cell cycle progression at G2/M (By similarity). [RUXE_YEAST] Involved in pre-mRNA splicing. Binds and is required for the stability of snRNA U1, U2, U4 and U5 which contain a highly conserved structural motif called the Sm binding site. Involved in cap modification. [CWC22_YEAST] May be involved in pre-mRNA splicing. [PRP19_YEAST] Involved in pre-mRNA splicing. Acts a central component of the NTC complex (or PRP19-associated complex) that associates to the spliceosome to mediate conformational rearrangement or to stabilize the structure of the spliceosome after U4 snRNA dissociation, which leads to spliceosome maturation. Involved in DNA repair. [PRP45_YEAST] Involved in pre-mRNA splicing. Associated with the spliceosome throughout the splicing reactions, until after the second catalytic step. Publication Abstract from PubMed Pre-mRNA splicing is executed by the spliceosome. Structural characterization of the catalytically activated complex (B( *)) is pivotal for understanding the branching reaction. In this study, we assembled the B( *) complexes on two different pre-mRNAs from Saccharomyces cerevisiae and determined the cryo-EM structures of four distinct B( *) complexes at overall resolutions of 2.9-3.8 A. The duplex between U2 small nuclear RNA (snRNA) and the branch point sequence (BPS) is discretely away from the 5'-splice site (5'SS) in the three B( *) complexes that are devoid of the step I splicing factors Yju2 and Cwc25. Recruitment of Yju2 into the active site brings the U2/BPS duplex into the vicinity of 5'SS, with the BPS nucleophile positioned 4 A away from the catalytic metal M2. This analysis reveals the functional mechanism of Yju2 and Cwc25 in branching. These structures on different pre-mRNAs reveal substrate-specific conformations of the spliceosome in a major functional state. Structures of the Catalytically Activated Yeast Spliceosome Reveal the Mechanism of Branching.,Wan R, Bai R, Yan C, Lei J, Shi Y Cell. 2019 Apr 4;177(2):339-351.e13. doi: 10.1016/j.cell.2019.02.006. Epub 2019, Mar 14. PMID:30879786 From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See Also Nucleoprotein 3D structures Pre-mRNA splicing factors 3D structures