About Semaphorin 4A
This gene encodes a member of the semaphorin family of soluble and transmembrane proteins. Semaphorins are involved in numerous functions, including axon guidance, morphogenesis, carcinogenesis, and immunomodulation. The encoded protein is a single-pass type I membrane protein containing an immunoglobulin-like C2-type domain, a PSI domain and a sema domain. It inhibits axonal extension by providing local signals to specify territories inaccessible for growing axons. It is an activator of T-cell-mediated immunity and suppresses vascular endothelial growth factor (VEGF)-mediated endothelial cell migration and proliferation in vitro and angiogenesis in vivo. Mutations in this gene are associated with retinal degenerative diseases including retinitis pigmentosa type 35 (RP35) and cone-rod dystrophy type 10 (CORD10). Multiple alternatively spliced transcript variants encoding different isoforms have been identified.[provided by RefSeq, Sep 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.