Anti-APH1B antibodies are used in the immunodetection of the protein aph-1 homolog B, gamma-secretase subunit. In humans, the canonical protein has a reported length of 257 amino acid residues and a mass of 28.5 kDa. Its subcellular localization is in the membrane. Alternative splicing is reported to yield 2 different isoforms for this protein. A member of a the APH-1 protein family, APH1B is a suspected subunit of the gamma-secretase complex, an endoprotease complex that catalyzes the intramembrane cleavage of integral proteins such as Notch receptors and APP (amyloid-beta precursor protein). Synonyms for this target antigen include APH1B gamma secretase subunit, anterior pharynx defective 1 homolog B, and gamma-secretase subunit APH-1B.