About TOP2A
This gene encodes a DNA topoisomerase, an enzyme that controls and alters the topologic states of DNA during transcription. This nuclear enzyme is involved in processes such as chromosome condensation, chromatid separation, and the relief of torsional stress that occurs during DNA transcription and replication. It catalyzes the transient breaking and rejoining of two strands of duplex DNA which allows the strands to pass through one another, thus altering the topology of DNA. Two forms of this enzyme exist as likely products of a gene duplication event. The gene encoding this form, alpha, is localized to chromosome 17 and the beta gene is localized to chromosome 3. The gene encoding this enzyme functions as the target for several anticancer agents and a variety of mutations in this gene have been associated with the development of drug resistance. Reduced activity of this enzyme may also play a role in ataxia-telangiectasia. [provided by RefSeq, Jul 2010]

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.