A theoretical investigation into the lipid interactions of m-calpain

The protease, m-calpain, has been implicated in a number of pathological conditions. The enzyme is a calcium-dependent heterodimer whose activity appears to be modulated by membrane interaction involving a segment, TAMRIL, located in domain V of the protein's small subunit. Based on a sequence analysis of m-calpain, using DWIH and hydrophobic moment plot based methodologies, we have shown that this segment may contribute to a lipid interactive, oblique orientated, alpha-helical region. Our results could form a basis for future studies on the postulated lipid modulation of m-calpain activity.