The ATP-dependent proteases Clp and FtsH from bacteria, as well as mit
ochondrial homologs of FtsH and Lon from yeast, may act as chaperones;
they mediate not only proteolysis, but also the insertion of proteins
into membranes and the disassembly or oligomerization of protein comp
lexes. The coordination of such processes with selective proteolysis m
ay function in the quality control of protein biogenesis.