abbreviation for ATPase associated with varied activities; any member of a family of conserved ATP-dependent proteases that mediate degradation of nonintegrated membrane proteins in bacteria, mitochondria, and chloroplasts. They form large complexes composed of identical or homologous subunits. Each subunit contains two transmembrane segments, an ATP-binding omain, and a metal-dependent catalytic domain. Mitochondria contain a matrix-facing AAA protease (m-AAA protease) and an intermembrane space-facing AAA protease (i-AAA protease). The
m-AAA protease is regulated by prohibitins. Paraplegin belongs to the AAA protease family.