A consensus amino-acid sequence repeat in Torpedo and mammalian Ca2+-dependent membrane-binding proteins

A group of calcium-binding proteins which bind to biomembranes has recently been identified in widely different cells and tissues (refs 1–7, reviewed in ref. 8). Three of these proteins (p70, p36 and p32.5) cross-react with antiserum to calelectrin, a Ca 2+ -binding protein (relative molecular mass 34,000 (34K)) from the ray Torpedo marmorata 3,4 , giving rise to their designation as calelectrin-related proteins 3 . We now report that calelectrin, p36 and p32.5 contain a 17-amino-acid consensus sequence which is conserved and present in multiple copies. We suggest that this sequence may be common to other members of this new group of Ca 2+ -binding proteins and may underlie their unusual mode of combination with biomembranes.