FIG. 3.

Processivity and primer extension of wild-type HIV-1 RT and the various RT mutants. As described in Materials and Methods, the presence of a poly(rC)·oligo(dG) trap binds the HIV-1 RT after it disassociates from the labeled template-primer. This limits the HIV-1 RT to one round of extension of the labeled primer and is a measure of processivity (on left side of figure). Without the trap, the HIV-1 RT can undergo multiple rounds of primer extension (on right side). The reactions were run for 10 min, and the reaction products were fractionated on a 6% polyacrylamide gel. The products were visualized by autoradiography. The scale on the left indicates the sizes of the products. WT, wild type.