Figure 3.

Effects of a position mutations on dimerization specificity. A subset of the mutants shown in Table 1 were tested for heterodimer formation by the in vivo competition test shown in Fig. 1. Combinations that formed heterodimers and were sensitive to superinfection are indicated by an s. Combinations that retained immunity are indicated by an i. Shadings are as in Fig. 2. Groups of leucine zippers with overlapping specificities are indicated by brackets on the right.