Figure 2.

EMSA analysis of the binding of purified Alx1-HD, Alx1-FL, and Alx1-ΔD2 proteins to the Sp-EMI/TM palindromic site and putative half sites. Binding specificity was confirmed by adding WT or mutant competitor. A, biotin-labeled probes containing the palindromic site, site A, or site B. B, biotin-labeled probes containing the palindromic site, site C, or site D. For the complete sequences of all probes used in this study, see Table S1. A sample of each purified protein was separated on SDS-PAGE gels and visualized by Coomassie staining (Fig. S1). Alx1-FL, full-length Alx1; Alx1-HD, Alx1 HD alone; Alx1ΔD2, a mutant form of Alx1 that lacks the D2 domain; D, dimer; F, free probe; M, monomer.