In humans, the prohibitin gene is located on chromosome 17q21, close to the ovarian and breast carcinoma susceptibility gene (BRAC1) locus. Prohibitin is a highly conserved protein that is thought to play a role in cell-cycle control, differentiation, senescence, and antiproliferative activity. The rat and mouse protein sequences are identical and differ from the human sequence by a single amino acid.
Microinjection of prohibitin mRNA into normal human diploid fibroblast-like cells and HeLa cells inhibited entry of the cells into the S phase of the cell cycle. Moreover, mutations or deletions in the prohibitin gene have been linked to some human breast and ovarian cancers, supporting the notion that pro-hibitin suppresses tumor progression as part of its antiproliferative function during cell-cycle control. Prohibitin is also implicated in controlling senescence and aging, a probable functional link to its antiproliferative function and cell-cycle control. Consistent with the proposed role of prohibitin in cell-cycle regulation, it has been demonstrated that this protein physically interacts with the retinoblastoma tumor-suppressor protein families both in vitro and in vivo. In addition, studies have shown that prohibitin is very effective in repressing E2F-mediated transcription, implying that this protein may be directly involved in transcriptional activation of specific genes.