ons of the anterior epithelium. AlphaB expression is detected in central epithelium and increases from the central to elongation zones, where epithelial cells differentiate into fiber cells. AlphaA, however, is not detected in the central epithelium. The relative proportion of alphaA and alphaB changes from a molar ratio of 1:3 in the pericentral and germative zones to a molar ratio of 3:1 in the elo