UniProtKB - Q46901 (CSE1_ECOLI)
CRISPR system Cascade subunit CasA
casA
Functioni
CRISPR (clustered regularly interspaced short palindromic repeat), is an adaptive immune system that provides protection against mobile genetic elements (viruses, transposable elements and conjugative plasmids). CRISPR clusters contain sequences complementary to antecedent mobile elements and target invading nucleic acids. CRISPR clusters are transcribed and processed into CRISPR RNA (crRNA).
A component of Cascade, which participates in CRISPR interference, the third stage of CRISPR immunity. Cascade binds both crRNA and in a sequence-specific manner negatively supercoiled dsDNA target. This leads to the formation of an R-loop in which the crRNA binds the target DNA, displacing the noncomplementary strand. Cas3 is recruited to Cascade, probably via interactions with CasA, nicks target DNA and then unwinds and cleaves the target, leading to DNA degradation and invader neutralization. CasA is not required for formation of Cascade, but probably enhances binding to and subsequent recognition of both target dsDNA and ssDNA.
GO - Molecular functioni
- DNA binding Source: EcoCyc
- RNA binding Source: EcoCyc
- zinc ion binding Source: EcoCyc
GO - Biological processi
- CRISPR-cas system Source: ComplexPortal
- defense response to virus Source: EcoCyc
Keywordsi
Molecular function | DNA-binding, RNA-binding |
Biological process | Antiviral defense |
Enzyme and pathway databases
BioCyci | EcoCyc:G7430-MONOMER |
Names & Taxonomyi
Protein namesi | Recommended name: CRISPR system Cascade subunit CasAAlternative name(s): CRISPR type I-E/Ecoli-associated protein CasA/Cse1 CRISPR-associated protein CasA/Cse1 |
Gene namesi | Name:casA Synonyms:cse1, ygcL Ordered Locus Names:b2760, JW2730 |
Organismi | Escherichia coli (strain K12) |
Taxonomic identifieri | 83333 [NCBI] |
Taxonomic lineagei | Bacteria › Proteobacteria › Gammaproteobacteria › Enterobacterales › Enterobacteriaceae › Escherichia › |
Proteomesi |
|
Pathology & Biotechi
Disruption phenotypei
Mutagenesis
Feature key | Position(s) | DescriptionActions | Graphical view | Length |
---|---|---|---|---|
Mutagenesisi | 129 | F → A: 80% increase in phage sensitivity; 500-fold decrease in affinity for target dsDNA. 1 Publication | 1 | |
Mutagenesisi | 130 | V → A: 20% increase in phage sensitivity; no change in binding of target dsDNA. 1 Publication | 1 | |
Mutagenesisi | 131 | N → A: 45% increase in phage sensitivity; 60-fold decrease in affinity for target dsDNA. 1 Publication | 1 |
PTM / Processingi
Molecule processing
Feature key | Position(s) | DescriptionActions | Graphical view | Length |
---|---|---|---|---|
ChainiPRO_0000169324 | 1 – 502 | CRISPR system Cascade subunit CasAAdd BLAST | 502 |
Proteomic databases
PaxDbi | Q46901 |
PRIDEi | Q46901 |
Expressioni
Inductioni
Interactioni
Subunit structurei
Part of the Cascade ribonucleoprotein complex, with stoichiometry CasA1,CasB2,CasC6,CasD1,CasE1-crRNA1.
Interacts directly with the 5' end of crRNA, CasB, CasD and CasE. Binding of target ssRNA or dsDNA causes a conformational change in the Cascade complex; CasA is required for high affinity target DNA binding.
Interacts with Cas3 once Cascade has recognized target DNA.
5 PublicationsProtein-protein interaction databases
BioGRIDi | 4260748, 358 interactors 851554, 1 interactor |
ComplexPortali | CPX-1005, Cascade complex |
DIPi | DIP-12128N |
IntActi | Q46901, 8 interactors |
STRINGi | 511145.b2760 |
Structurei
Secondary structure
3D structure databases
SMRi | Q46901 |
ModBasei | Search... |
PDBe-KBi | Search... |
Family & Domainsi
Sequence similaritiesi
Phylogenomic databases
eggNOGi | ENOG502Z880, Bacteria |
HOGENOMi | CLU_541555_0_0_6 |
InParanoidi | Q46901 |
Family and domain databases
CDDi | cd09669, Cse1_I-E, 1 hit |
InterProi | View protein in InterPro IPR013381, CRISPR-assoc_prot_Cse1 |
Pfami | View protein in Pfam PF09481, CRISPR_Cse1, 1 hit |
TIGRFAMsi | TIGR02547, casA_cse1, 1 hit |
i Sequence
Sequence statusi: Complete.
10 20 30 40 50
MNLLIDNWIP VRPRNGGKVQ IINLQSLYCS RDQWRLSLPR DDMELAALAL
60 70 80 90 100
LVCIGQIIAP AKDDVEFRHR IMNPLTEDEF QQLIAPWIDM FYLNHAEHPF
110 120 130 140 150
MQTKGVKAND VTPMEKLLAG VSGATNCAFV NQPGQGEALC GGCTAIALFN
160 170 180 190 200
QANQAPGFGG GFKSGLRGGT PVTTFVRGID LRSTVLLNVL TLPRLQKQFP
210 220 230 240 250
NESHTENQPT WIKPIKSNES IPASSIGFVR GLFWQPAHIE LCDPIGIGKC
260 270 280 290 300
SCCGQESNLR YTGFLKEKFT FTVNGLWPHP HSPCLVTVKK GEVEEKFLAF
310 320 330 340 350
TTSAPSWTQI SRVVVDKIIQ NENGNRVAAV VNQFRNIAPQ SPLELIMGGY
360 370 380 390 400
RNNQASILER RHDVLMFNQG WQQYGNVINE IVTVGLGYKT ALRKALYTFA
410 420 430 440 450
EGFKNKDFKG AGVSVHETAE RHFYRQSELL IPDVLANVNF SQADEVIADL
460 470 480 490 500
RDKLHQLCEM LFNQSVAPYA HHPKLISTLA LARATLYKHL RELKPQGGPS
NG
Mass spectrometryi
Sequence databases
Select the link destinations: EMBLi GenBanki DDBJi Links Updated | U29579 Genomic DNA Translation: AAA69270.1 U00096 Genomic DNA Translation: AAC75802.1 AP009048 Genomic DNA Translation: BAE76837.1 |
PIRi | D65057 |
RefSeqi | NP_417240.1, NC_000913.3 WP_001050401.1, NZ_LN832404.1 |
Genome annotation databases
EnsemblBacteriai | AAC75802; AAC75802; b2760 BAE76837; BAE76837; BAE76837 |
GeneIDi | 947222 |
KEGGi | ecj:JW2730 eco:b2760 |
PATRICi | fig|1411691.4.peg.3978 |
Similar proteinsi
Cross-referencesi
Sequence databases
Select the link destinations: EMBLi GenBanki DDBJi Links Updated | U29579 Genomic DNA Translation: AAA69270.1 U00096 Genomic DNA Translation: AAC75802.1 AP009048 Genomic DNA Translation: BAE76837.1 |
PIRi | D65057 |
RefSeqi | NP_417240.1, NC_000913.3 WP_001050401.1, NZ_LN832404.1 |
3D structure databases
Select the link destinations: PDBei RCSB PDBi PDBji Links Updated | PDB entry | Method | Resolution (Å) | Chain | Positions | PDBsum |
4QYZ | X-ray | 3.03 | A | 1-502 | [»] | |
4TVX | X-ray | 3.24 | I/U | 1-502 | [»] | |
4U7U | X-ray | 3.00 | A/M | 1-502 | [»] | |
5CD4 | X-ray | 3.20 | I/U | 1-502 | [»] | |
5H9E | X-ray | 3.21 | A | 1-502 | [»] | |
5H9F | X-ray | 2.45 | A | 1-502 | [»] | |
SMRi | Q46901 | |||||
ModBasei | Search... | |||||
PDBe-KBi | Search... |
Protein-protein interaction databases
BioGRIDi | 4260748, 358 interactors 851554, 1 interactor |
ComplexPortali | CPX-1005, Cascade complex |
DIPi | DIP-12128N |
IntActi | Q46901, 8 interactors |
STRINGi | 511145.b2760 |
Proteomic databases
PaxDbi | Q46901 |
PRIDEi | Q46901 |
Genome annotation databases
EnsemblBacteriai | AAC75802; AAC75802; b2760 BAE76837; BAE76837; BAE76837 |
GeneIDi | 947222 |
KEGGi | ecj:JW2730 eco:b2760 |
PATRICi | fig|1411691.4.peg.3978 |
Organism-specific databases
EchoBASEi | EB2920 |
Phylogenomic databases
eggNOGi | ENOG502Z880, Bacteria |
HOGENOMi | CLU_541555_0_0_6 |
InParanoidi | Q46901 |
Enzyme and pathway databases
BioCyci | EcoCyc:G7430-MONOMER |
Miscellaneous databases
PROi | PR:Q46901 |
Family and domain databases
CDDi | cd09669, Cse1_I-E, 1 hit |
InterProi | View protein in InterPro IPR013381, CRISPR-assoc_prot_Cse1 |
Pfami | View protein in Pfam PF09481, CRISPR_Cse1, 1 hit |
TIGRFAMsi | TIGR02547, casA_cse1, 1 hit |
MobiDBi | Search... |
Entry informationi
Entry namei | CSE1_ECOLI | |
Accessioni | Q46901Primary (citable) accession number: Q46901 Secondary accession number(s): Q2MA69 | |
Entry historyi | Integrated into UniProtKB/Swiss-Prot: | December 1, 2000 |
Last sequence update: | November 1, 1996 | |
Last modified: | February 23, 2022 | |
This is version 119 of the entry and version 1 of the sequence. See complete history. | ||
Entry statusi | Reviewed (UniProtKB/Swiss-Prot) | |
Annotation program | Prokaryotic Protein Annotation Program |
Miscellaneousi
Keywords - Technical termi
3D-structure, Reference proteomeDocuments
- PDB cross-references
Index of Protein Data Bank (PDB) cross-references - SIMILARITY comments
Index of protein domains and families