About D4 GDI
Members of the Rho (or ARH) protein family (see MIM 165390) and other Ras-related small GTP-binding proteins (see MIM 179520) are involved in diverse cellular events, including cell signaling, proliferation, cytoskeletal organization, and secretion. The GTP-binding proteins are active only in the GTP-bound state. At least 3 classes of proteins tightly regulate cycling between the GTP-bound and GDP-bound states: GTPase-activating proteins (GAPs), guanine nucleotide-releasing factors (GRFs), and GDP-dissociation inhibitors (GDIs). The GDIs, including ARHGDIB, decrease the rate of GDP dissociation from Ras-like GTPases (summary by Scherle et al., 1993 [PubMed 8356058]).[supplied by OMIM, Dec 2010]

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.