About CD123
The protein encoded by this gene is an interleukin 3 specific subunit of a heterodimeric cytokine receptor. The receptor is comprised of a ligand specific alpha subunit and a signal transducing beta subunit shared by the receptors for interleukin 3 (IL3), colony stimulating factor 2 (CSF2/GM-CSF), and interleukin 5 (IL5). The binding of this protein to IL3 depends on the beta subunit. The beta subunit is activated by the ligand binding, and is required for the biological activities of IL3. This gene and the gene encoding the colony stimulating factor 2 receptor alpha chain (CSF2RA) form a cytokine receptor gene cluster in a X-Y pseudoautosomal region on chromosomes X or Y. Alternatively spliced transcript variants encoding distinct isoforms have been found. [provided by RefSeq, Jun 2012]

About Alexa Fluor 546
Alexa Fluor™ 546 (AF546, Alexa 546) has an excitation peak at 556 nm and an emission peak at 573 nm, and is spectrally similar to Cy®3 (GE Healthcare), TRITC and iFluor® 555 (ATT Bioquest). Many flow cytometers are equipped with 532nm lasers, so while Alexa 546 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.