Fig. 5.

Analysis of the interactions between the three PABP homologues in vivo. (A) Distinct IP reactions were set up using total L. major cytoplasmic extract and affinity-purified antibodies directed against LmPABP1 (left), LmPABP2 (middle), and LmPABP3 (right), as well as the respective preimmune control sera (Control). Precipitated immunocomplexes, as well as the nonbound supernatant (NB) and the “Input” (equivalent to the amount of protein added to the IP reaction mixture), were then used in Western blot assays with the three distinct antisera, as indicated. (B) Effect of RNase treatment on the interaction between LmPABP2 and -3. Aliquots of the cytoplasmic extract were incubated in the presence or absence of 0.1 μg/μl of RNAse A (for 5 min at 37°C) prior to use in IP reactions carried out as for panel A with either the LmPABP2 or LmPABP3 antibody. For these assays, the IP of LmPABP2 was developed with the LmPABP3 antiserum and vice versa. On the left is shown the effect of the RNase treatment on the extract's RNAs.