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Fig. 6. Biochemical analysis of the degree of maturation of cell-cell contacts in
T98G and U373MG cell lines. (A) Western blot analysis of the amount of LIN-7
and ß-catenin recovered in the TX-100-soluble (S) and TX-100-insoluble
(I) fractions. T98G or U373MG glioblastoma cells grown to confluence were
extracted in TX-100. Equivalent volumes of the soluble or insoluble fractions
were separated by 10% SDS-PAGE and immunostained using the indicated
antibodies. (B) Total P-tyr content in T98G and U373MG cells.
5x105 cells were plated, cultured for 72 hours and extracted
in lysis buffer containing 0.02% SDS and 100 µM pervanadate. Five percent
of the cell lysate used in the immunoprecipitation experiments was probed for
P-tyr. (C,D) Tyrosine phosphorylation of
- and ß-catenin. The cell
lysates were immunoprecipitated with anti-
-(C) or anti-ß-catenin
(D) antibodies and probed for P-tyr. To confirm similar protein loading, 10%
of the immunoprecipitates were probed for
- (C) or ß-catenin (D).
Molecular weight standards expressed in kDa are indicated on the left.