1. IWASAKI, H., TAKAHAGI, M., SHIBA, T., NAKATA, A. AND SHINAGAWA, H.
Escherichia coli ruvC protein is an endonuclease that resolves the
EMBO J. 10(13) 4381-4389 (1991).
2. ARIYOSHI,M., VASSYLYEV, D.G., IWASAKI, H., FUJISHIMA, A.,
SHINAGAWA, H. AND MORIKAWA, K.
Preliminary crystallographic study of Escherichia coli ruvC protein:
an endonuclease specific for Holliday junctions.
J.MOL.BIOL. 241 281-282 (1994).
The Escherichia coli ruvC gene is involved in DNA repair and in the late
step of RecE and RecF pathway recombination . RuvC protein cleaves
cruciform junctions, which are formed by the extrusion of inverted repeat
sequences from a super-coiled plasmid and which are structurally analogous
to Holliday junctions, by introducing nicks into strands with the same
polarity. The nicked ends are ligated by E.coli or T4 DNA ligases. Analysis
of the cleavage sites suggests that DNA topology rather than a particular
sequence determines the cleavage site. RuvC protein also cleaves Holliday
junctions that are formed between gapped circular and linear duplex DNA by
the function of RecA protein. The active form of RuvC protein is a dimer.
This is mechanistically suited for an endonuclease involved in swapping DNA
strands at the crossover junctions. It is inferred that RuvC protein is an
endonuclease that resolves Holliday structures in vivo .
The structure of E.coli ruvC is a 3-layer alpha-beta sandwich containing
a 5-stranded beta-sheet sandwiched between 5 alpha-helices .
RSOLVASERUVC is a 5-element fingerprint that provides a signature for
crossover junction endodeoxyribonuclease ruvC. The fingerprint was derived
from an initial alignment of 5 sequences: the motifs were drawn from
conserved regions spanning the full alignment length - motif 1 spans the
first 2 strands; motif 2 encompasses strand 4 and the following loop;
motif 3 includes part of helix 2; motif 4 spans helices 3 and 4; and
motif 5 encompasses helix 5. A single iteration on OWL29.2 was required
to reach convergence, no further sequences being identified beyond the
starting set. A single partial match was found, SYCSLLLH82, a Synechocystis
homologue that matches motifs 1 and 4.
An update on SPTR37_9f identified a true set of 7 sequences, and 3