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Crystal Structure of a Eukaryotic GEN1 Resolving Enzyme Bound to DNA.

ABSTRACT: We present the crystal structure of the junction-resolving enzyme GEN1 bound to DNA at 2.5 Å resolution. The structure of the GEN1 protein reveals it to have an elaborated FEN-XPG family fold that is modified for its role in four-way junction resolution. The functional unit in the crystal is a monomer of active GEN1 bound to the product of resolution cleavage, with an extensive DNA binding interface for both helical arms. Within the crystal lattice, a GEN1 dimer interface juxtaposes two products, whereby they can be reconnected into a four-way junction, the structure of which agrees with that determined in solution. The reconnection requires some opening of the DNA structure at the center, in agreement with permanganate probing and 2-aminopurine fluorescence. The structure shows that a relaxation of the DNA structure accompanies cleavage, suggesting how second-strand cleavage is accelerated to ensure productive resolution of the junction.

SUBMITTER: Liu Y

PROVIDER: S-EPMC4695337 | biostudies-literature | 2015 Dec

REPOSITORIES: biostudies-literature

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Crystal Structure of a Eukaryotic GEN1 Resolving Enzyme Bound to DNA.

Liu Yijin Y Freeman Alasdair D J ADJ Déclais Anne-Cécile AC Wilson Timothy J TJ Gartner Anton A Lilley David M J DMJ

Cell reports 20151210 11

We present the crystal structure of the junction-resolving enzyme GEN1 bound to DNA at 2.5 Å resolution. The structure of the GEN1 protein reveals it to have an elaborated FEN-XPG family fold that is modified for its role in four-way junction resolution. The functional unit in the crystal is a monomer of active GEN1 bound to the product of resolution cleavage, with an extensive DNA binding interface for both helical arms. Within the crystal lattice, a GEN1 dimer interface juxtaposes two products ...[more]

PMID: 26686639

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