What is Holliday junction Resolvase?

(B) Canonical Holliday junction resolvases are dimeric enzymes that induce structural changes to the junction on binding, causing the junction to unfold. Resolution occurs by the introduction of two coordinated and symmetrically related nicks in strands of like polarity at, or very near, the branchpoint.

Which enzyme resolves the Holliday junction?

But the functional junction-resolving enzyme is the SLX1-SLX4-MUS81-EME1 complex.

What is a Holliday junction genetics?

Holliday junction, cross-shaped structure that forms during the process of genetic recombination, when two double-stranded DNA molecules become separated into four strands in order to exchange segments of genetic information.

What is Holliday junction and what is its purpose?

Purpose of holliday junctions Holliday junctions act as recognition signals near the ORCs of eukaryotic DNA during replication. Other proteins, such as MLL, WRN, 14-3-3, and DEK also show preferential binding.

How do you resolve a Holliday junction?

Cleavage, or resolution, of the Holliday junction can occur in two ways. Cleavage of the original set of strands leads to two molecules that may show gene conversion but not chromosomal crossover, while cleavage of the other set of two strands causes the resulting recombinant molecules to show crossover.

Which type of DNA is connected by Holliday junction?

Holliday junctions provide a covalent link between recombining DNA molecules and need to be removed prior to chromosome segregation at mitosis. Defects in their resolution lead to mitotic catastrophe, characterized by the formation of DNA breaks and chromosome aberrations.

Which type of DNA is connected by a Holliday junction?

How do you resolve Holliday junction?

How is Holliday junction resolved?

Holliday junction (HJ) resolution is essential for chromosome segregation at meiosis and the repair of stalled/collapsed replication forks in mitotic cells. All organisms possess nucleases that promote HJ resolution by the introduction of symmetrically related nicks in two strands at, or close to, the junction point.

What are the steps of Holliday junction formation?

The key features of the Holliday model are the formation of heteroduplex DNA; the creation of a cross bridge; its migration along the two heteroduplex strands, termed branch migration; the occurrence of mismatch repair; and the subsequent resolution, or splicing, of the intermediate structure to yield different types …

Which proteins are required for resolution of Holliday junction?

RuvC is a dimeric protein that promotes HJ resolution by introducing a pair of symmetrically related nicks in two strands that lie diametrically opposed across the junction point.

Which nuclease is responsible resolution of Holliday junction?

GEN1 protein
Mechanism of Holliday junction resolution by the human GEN1 protein.

What are the two families of Holliday junction resolvases?

In prokaryotes, Holliday junction resolvases fall into two families, integrases and nucleases, that are each structurally similar although their sequences are not conserved.

Why is the Holliday junction important to homologous recombination?

The Holliday junction is a key intermediate in homologous recombination, a biological process that increases genetic diversity by shifting genes between two chromosomes, as well as site-specific recombination events involving integrases.

Which is the correct orientation for a Holliday junction?

Holliday junctions with a nick, or break in one of the strands, at the junction point adopt a perpendicular orientation, and always prefer the stacking conformer that places the nick on a crossover strand rather than a helical strand.

What is the molecular structure of a stacked Holliday junction?

Molecular structure of a stacked Holliday junction, in which the four arms stack into two double-helical domains. Note how the blue and red strands remain roughly helical, while the green and yellow strands cross over between the two domains. Molecular structure of an unstacked Holliday junction.