Fig. 2.

Summary of resistance pathways that emerged after selection with the N44 peptide. The mutations and their locations in specific regions of gp120 and gp41 subunits of the envelope glycoprotein are shown. E560K and E648K are common early mutations that are used to define pathways I and II, respectively. Mutations contributing to pathways I and II are shown in white and shaded circles, respectively. Mutations shown in shaded rectangles contribute to both pathways. Arrows indicate pathway, not the order of emergence of the mutations.