Fig. 2. SLMAP3M1 is characterized by a unique N-terminal extension. (A) Amino acid composition of the N-terminal extension identified in SLMAP3. M1 (red) and M2 (blue) represent the two initiating methionines used to generate SLMAPs (Wigle et al., 1997). The consensus fork head associated (FHA) domain is demarcated by italics in bold print. Peptide sequence used to generate anti-SLMAP(N) rabbit antiserum is underlined (RLSRGSEESPPCEI). (B) Immunoblot analysis of SLMAP expression in NIH 3T3 cells. NIH 3T3 cells were lysed in RIPA buffer; 15 µg of total protein was separated by 10% SDS-PAGE then electrotransferred to PVDF membranes. Immunoblotting with anti-SLMAP(C) antibody (lane 1) or anti-SLMAP(N) antisera (lane 2) detected a single band at 91 kDa. Prior incubation of the anti-SLMAP(N) with SLMAP peptide abolished the immunoreactivity (lane 3). Positions of molecular mass standards are indicated (BENCHMARK Prestained Protein ladder, Gibco BRL).