[Studies of microtubule associated proteins in the liver--isolation of a 210 kDa microtubule associated protein from rabbit liver].
The biochemical characteristics and cellular localization of microtubule associated proteins (MAPs) were studied using rabbit liver. The MAPs fraction, isolated from rabbit liver crude extract by a modification of Vallee's method, consisted of several proteins, as identified by SDS-polyacrylamide gel electrophoresis. The most prominent of these was a 210 kDa protein (rabbit 210 kDa MAP). The molecular weight of rabbit 210 kDa MAP was distinct from that of the major brain MAPs, MAP1, MAP2 and Tau, isolated from rabbit brain crude extract by same method. Monoclonal antibodies (mAb) to this rabbit 210 kDa MAP were raised. Using immunoblotting method, we confirmed that anti-rabbit 210 kDa MAP mAb reacted to 210 kDa protein from rabbit liver excrude, while this mAb also reacted to 210 kDa protein from rabbit brain excrude. Immunofluorescent staining using fixed rabbit liver was carried out using these mAb. In frozen sections of the rabbit liver, the antigen related to mAb 7B10 was localised in the hepatic cells and epithelial cells of the bile duct but not in the smooth muscle cells and endothelial cells.