Intracellular Staining by Flow Cytometry
|Detection of AHR in C2C12 Mouse Cell Line by Flow Cytometry. C2C12 mouse myoblast cell line was stained with Sheep Anti-Mouse AHR Alexa Fluor® 488‑conjugated Antigen Affinity-purified Polyclonal Antibody (Catalog # IC6697G, filled histogram) or isotype control antibody (Catalog # IC016G, open histogram). To facilitate intracellular staining, cells were fixed with Flow Cytometry Fixation Buffer (Catalog # FC004) and permeabilized with Flow Cytometry Permeabilization/Wash Buffer I (Catalog # FC005). View our protocol for Staining Intracellular Molecules.|
AHR (Aryl-hydrocarbon receptor; also bHLHE76) is a 100-105 kDa member of the bHLH/PAS transcription factor family. It is widely expressed and serves many functions. First, it binds multiple xenobiotic chemicals in the cytoplasm. This induces dimerization with ARNT, translocation to the nucleus, and activation of P450 genes such as CYP1A1 and UGT1A6. Second, it appears to block cell cycle progression, possibly via a downregulation of CDK proteins. And third, it blocks apoptosis by interacting with E2F1, thus silencing Tap73 and Apaf1 genes. Mouse AHR precursor is 848 amino acids (aa) in length. It contains a nine aa prosegment, plus an 839 aa mature molecule that contains a DNA binding motif (aa 12-39), a bHLH region (aa 40-80), two PAS domains (aa 116-336) and one PAC segment that stabilizes the PAS domains (aa 342-383). There are multiple alleles for mouse AHR. One 95-97 kDa allele shows a premature truncation after Ser805, while a second 112 kDa allele shows a 41 aa substitution for aa 843-848. Over aa 706-805, mouse AHR shares 87% and 63% aa identity with rat and human AHR, respectively.