MXD3
Description
The MXD3 (MAX dimerization protein 3) is a protein-coding gene located on chromosome 5.
MXD3, encoded by the MXD3 gene on chromosome 5, is a basic helix-loop-helix protein that interacts with MAX. It competes with MYC for binding to MAX, forming a sequence-specific DNA-binding complex. This action makes MXD3 a transcriptional repressor, specifically expressed during the S phase of the cell cycle. MXD3 plays a role in normal neural development and has been implicated in the development of brain cancer. In medulloblastoma cells, MXD3 binds to E-box sequences, promoting cell proliferation at moderate levels, but leading to increased cell death and apoptosis at higher expression levels.
MXD3 functions as a transcriptional repressor. It forms a DNA-binding complex with MAX, recognizing the core sequence 5'-CAC[GA]TG-3'. By competing with MYC for MAX binding, MXD3 inhibits MYC-mediated gene transcription and suppresses MYC-dependent cell transformation.
MXD3 is also known as BHLHC13, MAD3, MYX.
