Skip Header

You are using a version of browser that may not display all the features of this website. Please consider upgrading your browser.
Protein

CRISPR system Cascade subunit CasE

Gene

casE

Organism
Escherichia coli (strain K12)
Status
Reviewed-Annotation score: -Experimental evidence at protein leveli

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).
CasE is required to process the pre-crRNA into single repeat-spacer units, with an 8-nt 5'-repeat DNA tag that may help other proteins recognize the crRNA. This subunit alone will cleave pre-crRNA, as will CasCDE or CasCE; cleavage does not require divalent metals or ATP. CasCDE alone is also able to form R-loops. Partially inhibits the cleavage of Holliday junctions by YgbT (Cas1). Yields a 5'-hydroxy group and a 2',3'-cyclic phosphate terminus.
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, nicks target DNA and then unwinds and cleaves the target, leading to DNA degradation and invader neutralization.

Cofactori

Note: Does not require a metal cofactor.1 Publication

GO - Molecular functioni

  • endoribonuclease activity Source: EcoCyc
  • RNA binding Source: EcoCyc

GO - Biological processi

  • defense response to virus Source: EcoCyc
  • RNA phosphodiester bond hydrolysis, endonucleolytic Source: EcoCyc
  • RNA processing Source: EcoCyc

Keywordsi

Molecular functionEndonuclease, Hydrolase, Nuclease, RNA-binding
Biological processAntiviral defense

Enzyme and pathway databases

BioCyciEcoCyc:G7426-MONOMER
MetaCyc:G7426-MONOMER

Names & Taxonomyi

Protein namesi
Recommended name:
CRISPR system Cascade subunit CasE (EC:3.1.-.-)
Alternative name(s):
CasE endoRNase
crRNA endonuclease
Gene namesi
Name:casE
Synonyms:cas6e, ygcH
Ordered Locus Names:b2756, JW2726
OrganismiEscherichia coli (strain K12)
Taxonomic identifieri83333 [NCBI]
Taxonomic lineageiBacteriaProteobacteriaGammaproteobacteriaEnterobacteralesEnterobacteriaceaeEscherichia
Proteomesi
  • UP000000318 Componenti: Chromosome
  • UP000000625 Componenti: Chromosome

Organism-specific databases

EcoGeneiEG13115 casE

Pathology & Biotechi

Disruption phenotypei

Loss of resistance to bacteriophage lambda infection, loss of plasmid silencing. Decreased levels of crRNA, increased levels of pre-crRNA, prevents pre-crRNA cleavage.3 Publications

Mutagenesis

Feature keyPosition(s)DescriptionActionsGraphical viewLength
Mutagenesisi20H → A: Loss of pre-crRNA cleavage. 2 Publications1

PTM / Processingi

Molecule processing

Feature keyPosition(s)DescriptionActionsGraphical viewLength
Initiator methionineiRemovedCurated
ChainiPRO_00001693212 – 199CRISPR system Cascade subunit CasEAdd BLAST198

Proteomic databases

PaxDbiQ46897
PRIDEiQ46897

Expressioni

Inductioni

Repressed by H-NS, activated by LeuO. Activated by the BaeSR two-component regulatory system, possibly due to envelope stress. Part of the casABCDE-ygbT-ygbF operon.3 Publications

Interactioni

Subunit structurei

Part of the Cascade ribonucleoprotein complex, with stoichiometry CasA1,CasB2,CasC6,CasD1,CasE1-crRNA1. Interacts directly with crRNA, CasA, CasB and CasC. Stable subcomplexes of CasBCDE-crRNA and CasCDE-crRNA also form, both of which are able to bind target dsDNA, and CasCDE is able to form R-loops. CasCDE and CasCE complexes have endonuclease activity. Interacts with YgbT (Cas1). Binding of target ssRNA or dsDNA causes a conformational change in the Cascade complex.7 Publications

Protein-protein interaction databases

BioGridi4261580, 317 interactors
DIPiDIP-12124N
IntActiQ46897, 5 interactors
STRINGi316385.ECDH10B_2924

Structurei

Secondary structure

1199
Legend: HelixTurnBeta strandPDB Structure known for this area
Show more details
Feature keyPosition(s)DescriptionActionsGraphical viewLength
Beta strandi2 – 8Combined sources7
Helixi10 – 12Combined sources3
Beta strandi13 – 15Combined sources3
Helixi16 – 24Combined sources9
Beta strandi37 – 46Combined sources10
Beta strandi49 – 58Combined sources10
Beta strandi64 – 73Combined sources10
Beta strandi83 – 90Combined sources8
Beta strandi93 – 97Combined sources5
Beta strandi107 – 109Combined sources3
Beta strandi111 – 115Combined sources5
Helixi119 – 130Combined sources12
Helixi131 – 133Combined sources3
Beta strandi134 – 143Combined sources10
Beta strandi147 – 152Combined sources6
Beta strandi156 – 158Combined sources3
Beta strandi161 – 170Combined sources10
Helixi172 – 181Combined sources10
Beta strandi183 – 185Combined sources3
Helixi187 – 189Combined sources3
Beta strandi194 – 198Combined sources5

3D structure databases

Select the link destinations:
PDBei
RCSB PDBi
PDBji
Links Updated
PDB entryMethodResolution (Å)ChainPositionsPDBsum
4DZDX-ray2.00A1-199[»]
4QYZX-ray3.03K1-199[»]
4TVXX-ray3.24A/M1-199[»]
4U7UX-ray3.00D/P1-199[»]
5CD4X-ray3.20A/M1-199[»]
5H9EX-ray3.21K1-199[»]
5H9FX-ray2.45K1-199[»]
ProteinModelPortaliQ46897
SMRiQ46897
ModBaseiSearch...
MobiDBiSearch...

Family & Domainsi

Sequence similaritiesi

Phylogenomic databases

eggNOGiENOG4108Y7V Bacteria
ENOG410ZWC5 LUCA
HOGENOMiHOG000015851
InParanoidiQ46897
KOiK19126
OMAiKSRQMIQ

Family and domain databases

InterProiView protein in InterPro
IPR010179 CRISPR-assoc_prot_Cse3
PfamiView protein in Pfam
PF08798 CRISPR_assoc, 1 hit
SMARTiView protein in SMART
SM01101 CRISPR_assoc, 1 hit
TIGRFAMsiTIGR01907 casE_Cse3, 1 hit

Sequencei

Sequence statusi: Complete.

Sequence processingi: The displayed sequence is further processed into a mature form.

Q46897-1 [UniParc]FASTAAdd to basket

« Hide

        10         20         30         40         50
MYLSKVIIAR AWSRDLYQLH QGLWHLFPNR PDAARDFLFH VEKRNTPEGC
60 70 80 90 100
HVLLQSAQMP VSTAVATVIK TKQVEFQLQV GVPLYFRLRA NPIKTILDNQ
110 120 130 140 150
KRLDSKGNIK RCRVPLIKEA EQIAWLQRKL GNAARVEDVH PISERPQYFS
160 170 180 190
GDGKSGKIQT VCFEGVLTIN DAPALIDLVQ QGIGPAKSMG CGLLSLAPL
Length:199
Mass (Da):22,293
Last modified:November 1, 1996 - v1
Checksum:i1D5C060DD5FCAFAD
GO

Mass spectrometryi

Molecular mass is 22364.7±1.1 Da from positions 2 - 199. 1 Publication

Sequence databases

Select the link destinations:
EMBLi
GenBanki
DDBJi
Links Updated
U29579 Genomic DNA Translation: AAA69266.1
U00096 Genomic DNA Translation: AAC75798.1
AP009048 Genomic DNA Translation: BAE76833.1
PIRiH65056
RefSeqiNP_417236.1, NC_000913.3
WP_000281400.1, NZ_LN832404.1

Genome annotation databases

EnsemblBacteriaiAAC75798; AAC75798; b2756
BAE76833; BAE76833; BAE76833
GeneIDi947226
KEGGiecj:JW2726
eco:b2756
PATRICifig|1411691.4.peg.3982

Similar proteinsi

Entry informationi

Entry nameiCAS6_ECOLI
AccessioniPrimary (citable) accession number: Q46897
Secondary accession number(s): Q2MA73
Entry historyiIntegrated into UniProtKB/Swiss-Prot: July 15, 1999
Last sequence update: November 1, 1996
Last modified: April 25, 2018
This is version 112 of the entry and version 1 of the sequence. See complete history.
Entry statusiReviewed (UniProtKB/Swiss-Prot)
Annotation programProkaryotic Protein Annotation Program

Miscellaneousi

Keywords - Technical termi

3D-structure, Complete proteome, Reference proteome
UniProt is an ELIXIR core data resource
Main funding by: National Institutes of Health