Fig. 4. Adenoviruses expressing mutant forms of Rho GTPases induce specific expression of each protein in ECs. ECs were infected with either DN or CA Rho, Rac or Cdc42 adenoviruses. Cells were allowed 24 hours to express proteins before placing them in three-dimensional collagen matrices. Cultures were allowed to proceed for 24 hours prior to preparing extracts. Samples were loaded onto 12% SDS-PAGE gels, blotted to PVDF and probed with GTPase-specific antibodies. Infection with GFP control adenovirus showed no signal (not shown).