[English] 日本語
Yorodumi
- EMDB-18723: Cryo-EM structure of the cross-exon pre-B complex (tri-snRNP region) -

+
Open data


ID or keywords:

Loading...

-
Basic information

Entry
Database: EMDB / ID: EMD-18723
TitleCryo-EM structure of the cross-exon pre-B complex (tri-snRNP region)
Map data
Sample
  • Complex: tri-snRNP-part-of-the cross-exon pre-B complex
Keywordsspliceosome / SPLICING
Biological speciesHomo sapiens (human)
Methodsingle particle reconstruction / cryo EM / Resolution: 4.5 Å
AuthorsZhang Z / Kumar V / Dybkov O / Will CL / Zhong J / Ludwig S / Urlaub H / Kastner B / Stark H / Luehrmann R
Funding support Germany, 1 items
OrganizationGrant numberCountry
German Research Foundation (DFG) Germany
CitationJournal: Nature / Year: 2024
Title: Structural insights into the cross-exon to cross-intron spliceosome switch.
Authors: Zhenwei Zhang / Vinay Kumar / Olexandr Dybkov / Cindy L Will / Jiayun Zhong / Sebastian E J Ludwig / Henning Urlaub / Berthold Kastner / Holger Stark / Reinhard Lührmann /
Abstract: Early spliceosome assembly can occur through an intron-defined pathway, whereby U1 and U2 small nuclear ribonucleoprotein particles (snRNPs) assemble across the intron. Alternatively, it can occur ...Early spliceosome assembly can occur through an intron-defined pathway, whereby U1 and U2 small nuclear ribonucleoprotein particles (snRNPs) assemble across the intron. Alternatively, it can occur through an exon-defined pathway, whereby U2 binds the branch site located upstream of the defined exon and U1 snRNP interacts with the 5' splice site located directly downstream of it. The U4/U6.U5 tri-snRNP subsequently binds to produce a cross-intron (CI) or cross-exon (CE) pre-B complex, which is then converted to the spliceosomal B complex. Exon definition promotes the splicing of upstream introns and plays a key part in alternative splicing regulation. However, the three-dimensional structure of exon-defined spliceosomal complexes and the molecular mechanism of the conversion from a CE-organized to a CI-organized spliceosome, a pre-requisite for splicing catalysis, remain poorly understood. Here cryo-electron microscopy analyses of human CE pre-B complex and B-like complexes reveal extensive structural similarities with their CI counterparts. The results indicate that the CE and CI spliceosome assembly pathways converge already at the pre-B stage. Add-back experiments using purified CE pre-B complexes, coupled with cryo-electron microscopy, elucidate the order of the extensive remodelling events that accompany the formation of B complexes and B-like complexes. The molecular triggers and roles of B-specific proteins in these rearrangements are also identified. We show that CE pre-B complexes can productively bind in trans to a U1 snRNP-bound 5' splice site. Together, our studies provide new mechanistic insights into the CE to CI switch during spliceosome assembly and its effect on pre-mRNA splice site pairing at this stage.
History
DepositionOct 24, 2023-
Header (metadata) releaseJun 26, 2024-
Map releaseJun 26, 2024-
UpdateJul 10, 2024-
Current statusJul 10, 2024Processing site: PDBe / Status: Released

-
Structure visualization

Supplemental images

emd_18723.png

Downloads & links

-
Map

FileDownload / File: emd_18723.map.gz / Format: CCP4 / Size: 421.9 MB / Type: IMAGE STORED AS FLOATING POINT NUMBER (4 BYTES)
Projections & slices

Image control

Size
Brightness
Contrast
Others
AxesZ (Sec.)Y (Row.)X (Col.)
1.35 Å/pix.
x 480 pix.
= 648. Å		1.35 Å/pix.
x 480 pix.
= 648. Å		1.35 Å/pix.
x 480 pix.
= 648. Å

Surface

Projections

Slices (1/3)

Slices (1/2)

Slices (2/3)

Images are generated by Spider.

Voxel sizeX=Y=Z: 1.35 Å
Density

Histogram

Histogram (log scale)
Contour LevelBy AUTHOR: 0.015
Minimum - Maximum-0.02754971 - 0.14618511
Average (Standard dev.)0.00090378727 (±0.008176034)
SymmetrySpace group: 1
Details

EMDB XML:

Map geometry
Axis orderXYZ
Origin000
Dimensions480480480
Spacing480480480
CellA=B=C: 648.0 Å
α=β=γ: 90.0 °

-
Supplemental data

-
Half map: #1

Fileemd_18723_half_map_1.map
Projections & Slices
AxesZYX

Projections

Slices (1/2)
Density Histograms

Histogram

Histogram (log scale)

-
Half map: #2

Fileemd_18723_half_map_2.map
Projections & Slices
AxesZYX

Projections

Slices (1/2)
Density Histograms

Histogram

Histogram (log scale)

-
Sample components

-
Entire : tri-snRNP-part-of-the cross-exon pre-B complex

EntireName: tri-snRNP-part-of-the cross-exon pre-B complex
Components
  • Complex: tri-snRNP-part-of-the cross-exon pre-B complex

-
Supramolecule #1: tri-snRNP-part-of-the cross-exon pre-B complex

SupramoleculeName: tri-snRNP-part-of-the cross-exon pre-B complex / type: complex / ID: 1 / Parent: 0
Source (natural)Organism: Homo sapiens (human)

-
Experimental details

-
Structure determination

Methodcryo EM
Processingsingle particle reconstruction
Aggregation stateparticle

-
Sample preparation

BufferpH: 7.9
VitrificationCryogen name: ETHANE

-
Electron microscopy

MicroscopeFEI TITAN KRIOS
Image recordingFilm or detector model: FEI FALCON III (4k x 4k) / Average electron dose: 45.0 e/Å2
Electron beamAcceleration voltage: 300 kV / Electron source: FIELD EMISSION GUN
Electron opticsIllumination mode: FLOOD BEAM / Imaging mode: BRIGHT FIELD / Nominal defocus max: 5.0 µm / Nominal defocus min: 1.5 µm
Experimental equipment
Model: Titan Krios / Image courtesy: FEI Company

-
Image processing

Startup modelType of model: OTHER / Details: ab initio
Final reconstructionResolution.type: BY AUTHOR / Resolution: 4.5 Å / Resolution method: FSC 0.143 CUT-OFF / Number images used: 279781
Initial angle assignmentType: MAXIMUM LIKELIHOOD
Final angle assignmentType: MAXIMUM LIKELIHOOD

+
About Yorodumi

-
News

-
Feb 9, 2022. New format data for meta-information of EMDB entries

New format data for meta-information of EMDB entries

  • Version 3 of the EMDB header file is now the official format.
  • The previous official version 1.9 will be removed from the archive.

Related info.:EMDB header

External links:wwPDB to switch to version 3 of the EMDB data model

-
Aug 12, 2020. Covid-19 info

Covid-19 info

URL: https://pdbj.org/emnavi/covid19.php

New page: Covid-19 featured information page in EM Navigator.

Related info.:Covid-19 info / Mar 5, 2020. Novel coronavirus structure data

+
Mar 5, 2020. Novel coronavirus structure data

Novel coronavirus structure data

Related info.:Yorodumi Speices / Aug 12, 2020. Covid-19 info

External links:COVID-19 featured content - PDBj / Molecule of the Month (242)：Coronavirus Proteases

+
Jan 31, 2019. EMDB accession codes are about to change! (news from PDBe EMDB page)

EMDB accession codes are about to change! (news from PDBe EMDB page)

  • The allocation of 4 digits for EMDB accession codes will soon come to an end. Whilst these codes will remain in use, new EMDB accession codes will include an additional digit and will expand incrementally as the available range of codes is exhausted. The current 4-digit format prefixed with “EMD-” (i.e. EMD-XXXX) will advance to a 5-digit format (i.e. EMD-XXXXX), and so on. It is currently estimated that the 4-digit codes will be depleted around Spring 2019, at which point the 5-digit format will come into force.
  • The EM Navigator/Yorodumi systems omit the EMD- prefix.

Related info.:Q: What is EMD? / ID/Accession-code notation in Yorodumi/EM Navigator

External links:EMDB Accession Codes are Changing Soon! / Contact to PDBj

+
Jul 12, 2017. Major update of PDB

Major update of PDB

  • wwPDB released updated PDB data conforming to the new PDBx/mmCIF dictionary.
  • This is a major update changing the version number from 4 to 5, and with Remediation, in which all the entries are updated.
  • In this update, many items about electron microscopy experimental information are reorganized (e.g. em_software).
  • Now, EM Navigator and Yorodumi are based on the updated data.

External links:wwPDB Remediation / Enriched Model Files Conforming to OneDep Data Standards Now Available in the PDB FTP Archive

-
Yorodumi

Thousand views of thousand structures

  • Yorodumi is a browser for structure data from EMDB, PDB, SASBDB, etc.
  • This page is also the successor to EM Navigator detail page, and also detail information page/front-end page for Omokage search.
  • The word "yorodu" (or yorozu) is an old Japanese word meaning "ten thousand". "mi" (miru) is to see.

Related info.:EMDB / PDB / SASBDB / Comparison of 3 databanks / Yorodumi Search / Aug 31, 2016. New EM Navigator & Yorodumi / Yorodumi Papers / Jmol/JSmol / Function and homology information / Changes in new EM Navigator and Yorodumi

Read more