About OPG
The protein encoded by this gene is a member of the TNF-receptor superfamily. This protein is an osteoblast-secreted decoy receptor that functions as a negative regulator of bone resorption. This protein specifically binds to its ligand, osteoprotegerin ligand, both of which are key extracellular regulators of osteoclast development. Studies of the mouse counterpart also suggest that this protein and its ligand play a role in lymph-node organogenesis and vascular calcification. Alternatively spliced transcript variants of this gene have been reported, but their full length nature has not been determined. [provided by RefSeq, Jul 2008]

About Alexa Fluor 555
Alexa Fluor™ 555 (AF555, Alexa 555) has an excitation peak at 555 nm and an emission peak at 565 nm, and is spectrally similar to Cy®3 (GE Healthcare), TRITC, iFluor® 555 (ATT Bioquest) and iFluor® 560 (ATT Bioquest). Many flow cytometers are equipped with 532nm lasers, so while Alexa 555 can be used for flow cytometry, PE is more commonly used due to its brightness and spectral characteristics. This dye is commonly used for fluorescence microscopy applications.