FEATURES

FAMILY

DESCRIPTION

Also known as CAS5_ECOLI, casD, cas5, ygcI. 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, nicks target DNA and then unwinds and cleaves the target, leading to DNA degradation and invader neutralization. CasCDE alone is also able to form R-loops. Part of the Cascade ribonucleoprotein complex, with stoichiometry CasA(1), CasB(2), CasC(6), CasD(1), CasE(1)-crRNA(1). Interacts directly with CasA and CasC. Stable subcomplexes of CasBCDE-crRNA and CasCDE-crRNA also form, both of which are able to bind target dsDNA, and at least CasCDE is able to form R-loops. CasCDE and CasCE complexes have endonuclease activity. Binding of target ssRNA or dsDNA causes a conformational change in the Cascade complex.

EXTERNAL LINKS

casD

Mutations

Mutation(s) distribution

Mutations table