Acts as a component of the m-AAA protease complex which is a ATP-dependent metalloprotease mediating degradation of non-assembled mitochondrial inner membrane proteins. The complex is necessary for the assembly of mitochondrial respiratory chain and ATPase complexes. Function both in post-translational assembly and in the turnover of mistranslated or misfolded polypeptides. Binds 1 zinc ion per subunit. Component of the 850 kDa m-AAA protease complex (YTA10-12) which consists of multiple copies of RCA1 AND AFG3. Present with 11500 molecules/cell in log phase SD medium. In the N-terminal section; belongs to the AAA ATPase family. In the C-terminal section; belongs to the peptidase M41 family.