STOML2 is similar in sequence to stomatin. It is a 356 amino acid protein with a calculated molecular mass of 38.5 kDa. STOML2 has 3 potential initiator sites, all sharing the same open reading frame. The STOML2 protein contains the cognate stomatin family consensus sequence, but it lacks the characteristic N-terminal hydrophobic domain and palmitoylation consensus sequence. STOML2 shares greatest sequence homology with stomatin and SLP1 in a region predicted to contain beta sheet and alpha helix structures. Northern blot analysis detected a 1.5 kb STOML2 transcript in all tissues examined, with highest levels in heart, liver, and pancreas. Western blot analysis detected STOML2 at apparent molecular masses of 45.5 kDa or 44.6 kDa in all human and mammalian cell lines and tissues examined, including red blood cells. Some cells also showed a faint band at about 34.3 kDa, which may represent translation from an alternate initiation site.
