Fig. 4. Expression of chagasin RNA in T. cruzi. Total RNA (20 µg) from trypomastigotes (lane 1), epimastigotes (lane 2) or amastigotes (lane 3) were separated in a 2% agarose-formaldehyde gel, transferred onto nylon membranes and probed with [-³²P]chagasin cDNA in 5x SSC, 5x Denhardt’s, 1% SDS, 50 µg/ml salmon sperm DNA, 50% formamide at 42°C, overnight, washed three times with 0.2xSSPE, 0.1% SDS, and exposed overnight at –70°C. Left panel: Ethidium bromide staining of the gel. Right panel: Autoradiograph. The approximate position of co-eletrophoresed RNA molecular weight marker is indicated on the right.