The tertiary structure of the four-way DNA junction affords protection against DNase I cleavage.

AUTOR(ES)

Murchie, A I

RESUMO

The accessibility of phosphodiester bonds in the DNA of four-way helical junctions has been probed with the nuclease DNase I. Regions of protection were observed on all four strands of the junctions, that tended to be longer on the strands that are exchanged between the coaxially stacked pairs of helices. The protected regions on the continuous strands of the stacked helices were not located exactly at the junction, but were displaced towards the 3' side of the strand. This is the region of backbone that becomes located in the major groove of the opposed helix in the non-crossed, right-handed structure for the junction, and might therefore be predicted to be protected against cleavage by an enzyme. However, the major grooves of the structure remain accessible to the much smaller probe dimethyl sulphate.

Documentos Relacionados

• The complex between a four-way DNA junction and T7 endonuclease I
• The stereochemistry of a four-way DNA junction: a theoretical study.
• Cleavage of a four-way DNA junction by a restriction enzyme spanning the point of strand exchange.
• Crystal structure of a DNA decamer showing a novel pseudo four-way helix-helix junction.
• Interaction of the resolving enzyme YDC2 with the four-way DNA junction.