About gamma H2AX
Histones are basic nuclear proteins that are responsible for the nucleosome structure of the chromosomal fiber in eukaryotes. Two molecules of each of the four core histones (H2A, H2B, H3, and H4) form an octamer, around which approximately 146 bp of DNA is wrapped in repeating units, called nucleosomes. The linker histone, H1, interacts with linker DNA between nucleosomes and functions in the compaction of chromatin into higher order structures. This gene encodes a replication-independent histone that is a member of the histone H2A family, and generates two transcripts through the use of the conserved stem-loop termination motif, and the polyA addition motif. [provided by RefSeq, Oct 2015]

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.