Unknown

Dataset Information

0

Flap endonuclease 1 mechanism analysis indicates flap base binding prior to threading.


ABSTRACT: FEN1 cleaves 5' flaps at their base to create a nicked product for ligation. FEN1 has been reported to enter the flap from the 5'-end and track to the base. Current binding analyses support a very different mechanism of interaction with the flap substrate. Measurements of FEN1 binding to a flap substrate show that the nuclease binds with similar high affinity to the base of a long flap even when the 5'-end is blocked with biotin/streptavidin. However, FEN1 bound to a blocked flap is more sensitive to sequestration by a competing substrate. These results are consistent with a substrate interaction mechanism in which FEN1 first binds the flap base and then threads the flap through an opening in the protein from the 5'-end to the base for cleavage. Significantly, when the unblocked flap length is reduced from five to two nucleotides, FEN1 can be sequestered from the substrate to a similar extent as a blocked, long flap substrate. Apparently, interactions related to threading occur only when the flap is greater than two to four nucleotides long, implying that short flaps are cleaved without a threading requirement.

SUBMITTER: Gloor JW 

PROVIDER: S-EPMC2966106 | biostudies-literature | 2010 Nov

REPOSITORIES: biostudies-literature

altmetric image

Publications

Flap endonuclease 1 mechanism analysis indicates flap base binding prior to threading.

Gloor Jason W JW   Balakrishnan Lata L   Bambara Robert A RA  

The Journal of biological chemistry 20100825 45


FEN1 cleaves 5' flaps at their base to create a nicked product for ligation. FEN1 has been reported to enter the flap from the 5'-end and track to the base. Current binding analyses support a very different mechanism of interaction with the flap substrate. Measurements of FEN1 binding to a flap substrate show that the nuclease binds with similar high affinity to the base of a long flap even when the 5'-end is blocked with biotin/streptavidin. However, FEN1 bound to a blocked flap is more sensiti  ...[more]

Similar Datasets

| S-EPMC4939078 | biostudies-literature
| S-EPMC3345168 | biostudies-literature
| S-EPMC2755943 | biostudies-literature
| S-EPMC3086263 | biostudies-literature
| S-EPMC1865060 | biostudies-literature
| S-EPMC5358979 | biostudies-literature
| S-EPMC2875029 | biostudies-literature
| S-EPMC2836044 | biostudies-literature
| S-EPMC2367431 | biostudies-literature
| S-EPMC7609719 | biostudies-literature