About SOX21
SRY-related HMG-box (SOX) genes encode a family of DNA-binding proteins containing a 79-amino acid HMG (high mobility group) domain that shares at least 50% sequence identity with the DNA-binding HMG box of the SRY protein (MIM 480000). SOX proteins are divided into 6 subgroups based on sequence similarity within and outside of the HMG domain. For additional background information on SOX genes, see SOX1 (MIM 602148).[supplied by OMIM, Apr 2004]

About APC
Allophycocyanin (APC) is a fluorescent protein derived from cyanobacteria and red algae and a potent donor fluorophore to create tandem dyes that can be excited off the 633-640 nm laser. APC has an excitation peak at 650 nm and a emission peak at 660 nm.