Fig. 9. Summary of binding activities of different LAP2 isoforms. (A) Diagram of the constant region of Xenopus LAP2 (LAP2-c), Xenopus LAP2 isoforms 2, 3 and 4 (termed iso2-cv, iso3-cv and iso4-cv, respectively) and the variable domains of isoforms 2 and 3 (iso2-v and iso3-v). Exons are numbered according to the mouse LAP2 gene (Berger et al., 1996); letters correspond to additional exons identified in Xenopus LAP2 isoforms (Gant et al., 1999). (B) Summary of binding results in this study. Binding to BAF (relative affinities as determined in Figure 7): +++, wild-type binding to BAF; ++, 3-fold reduced binding to BAF; +, 9-fold reduced binding to BAF; –, no detectable binding to BAF. Binding to BAF⋅DNA complexes and to DNA: binding was assayed qualitatively in five independent experiments, including that shown in Figure 8. PI, isolectric point; the calculated net charges at pH 8.3 (native gel conditions) are: LAP2-c, –4.0; iso2-cv, –5.0; iso2-v, –0.6; iso3-cv, –7.7; iso3-v, –3.3; iso4-cv, +1.0.