Major vault protein, also known as lung resistance-related protein is a protein that in humans is encoded by the MVP gene. 78 copies of the protein assemble into the large compartments called vaults.

Function

This gene encodes the major vault protein which is a lung infection resistance-related protein. Vaults are multi-subunit structures that may be involved in nucleo-cytoplasmic transport. Major vault protein comprises 70% of vaults which also contain vPARP and TEP1. This protein mediates drug resistance, perhaps via a transport process. It is widely distributed in normal tissues and overexpressed in multidrug-resistant cancer cells. The protein overexpression is a potentially useful marker of clinical drug resistance. This gene produces two transcripts by using two alternative exon 2 sequences; however, the open reading frames are the same in both transcripts.

Interactions

Major vault protein coimmunoprecipitates with the human estrogen receptor and treatment with estradiol increases major vault protein associated with the estrogen receptor in nuclear extracts. Major vault protein has been shown to interact with estrogen receptor alpha, PTEN and PARP4.