Golgi membrane association of αB-crystallin is susceptible to BFA. The two anatomic domains, (A)E+SC (−BFA = 4.77 mg protein; +BFA = 2.62 mg) and (B) FM (−BFA = 6.01 mg; +BFA = 3.5 mg) were fractionated as described. The distribution of αB-crystallin in P10 lenses is similar to that obtained with P20 lenses. In E+SC gradients, note that the distribution of αB-crystallin changes, shifting to the top of the gradient on BFA treatment (A, +BFA). Similarly, a marked loss of Golgi-associated αB-crystallin is seen in the FM gradients (asterisks) (B, compare −BFA with +BFA). Calnexin (an ER marker) is undetectable, whereas there is no effect on the mitochondrial marker cytochrome c (Cyto-C). Only anti–GM130 immunoblots from −BFA are shown. GM130 is undetectable in +BFA gradients.