About RNA Pol II RPB3
This gene encodes the third largest subunit of RNA polymerase II, the polymerase responsible for synthesizing messenger RNA in eukaryotes. The product of this gene contains a cysteine rich region and exists as a heterodimer with another polymerase subunit, POLR2J. These two subunits form a core subassembly unit of the polymerase. A pseudogene has been identified on chromosome 21. [provided by RefSeq, Jul 2008]

About FITC
Fluorescein isothiocyanate (FITC) has an excitation peak at 495 nm and an emission peak at 519 nm. The name FITC is a misnomer in that the isothiocyanate is a reactive form of this dye. Once FITC is conjugated to an antibody, it is simply Fluorescein conjugated. FITC is one of the most widely used dyes for fluorescent applications, therefore most instruments come standard with a 488 nm laser and FITC filter set up. FITC is commonly conjugated to secondary antibodies and used in applications such as flow cytometry, immunocytochemistry, and immunohistochemistry. FITC is relatively dim, sensitive to photobleaching and it is susceptible to changes is pH. There are better performing alternatives to FITC, like Vio®Bright 515, Alexa Fluor™ 488, iFluor® 488, CF®488A and DY-488. FITC is a long-time generic dye with no sole manufacturer or trademark.