About FEN1
The protein encoded by this gene removes 5' overhanging flaps in DNA repair and processes the 5' ends of Okazaki fragments in lagging strand DNA synthesis. Direct physical interaction between this protein and AP endonuclease 1 during long-patch base excision repair provides coordinated loading of the proteins onto the substrate, thus passing the substrate from one enzyme to another. The protein is a member of the XPG/RAD2 endonuclease family and is one of ten proteins essential for cell-free DNA replication. DNA secondary structure can inhibit flap processing at certain trinucleotide repeats in a length-dependent manner by concealing the 5' end of the flap that is necessary for both binding and cleavage by the protein encoded by this gene. Therefore, secondary structure can deter the protective function of this protein, leading to site-specific trinucleotide expansions. [provided by RefSeq, Jul 2008]

About Janelia Fluor 549
Janelia Fluor® 549 was developed at the Janelia Campus of the Howard Hughes Medical Institute but is commercialized by other vendors. The Janelia Fluor®s family is unique in that the fluorophores are cell-permeable and are available in photoactivatable forms. These fluorophores were developed for super-resolution microscopy (STED, PALM and STORM) and live-cell microscopy in the HaloTag and SNAP-tag versions. Janelia Fluor® 549 has an excitation peak at 549 nm and an emission peak at 571 nm.