FIG. 4.

Amino acid substitutions that affect UNC-86 ternary complex formation in yeast. The amino acid sequences of POU_S and POU_HD of UNC-86 (3), Oct-1 (32), and Pit-1 (20) are shown, with labeled boxes below the sequences depicting the α helices in the corresponding POU domain. Symbols: ★, mutation that interferes only with MEC-3–GAD coactivation (class I); □, mutation that influences transcriptional activation by UNC-86 (class II); ●, mutation that interferes with DNA binding and MEC-3–GAD coactivation (class III); ■, mutation that does not affect UNC-86 function.