The prohibitins (Phb1 and Phb2) are outer mitochondrial membrane proteins that form a large complex. The antibodies I've used against them are very robust (though Phb1 and 2 are both detected).

Thank you,  Simon. Could you tell me from which company do  you use this antibody?

Hi, I guess when you say unspecific would be because you have signal of the antibody in non-mitochondrial fraction in WB. If I am true maybe is because you broke some mitochondria during isolation and could have parts of them in the cytosol. For MOM I used TOM20 from Sigma working pretty good in WB and IF. Hope it works