Fig. 1. Alanine substitution mutagenesis of the constant region (residues 1–165) of Xenopus LAP2 (LAP2-c). (A) The amino acid sequence of LAP2-c. Black-shaded residues were replaced by alanine; each set of mutations is indicated by a numbered bar. Mutant cluster m19 includes a tyrosine rather than alanine substitution for the second asparagine. The LEM domain (residues 91–138) is shaded gray. Arrows marked M and E indicate the start of homology to the N-termini of human MAN1 and emerin, respectively. (B) Coomassie Blue-stained native 8–25% acrylamide gel of purified wild-type LAP2-c and LAP2-c mutants, numbered as shown in (A). (C) The same proteins run on SDS-containing denaturing 8–25% acrylamide gels, stained with Coomassie Blue.