Recombinant Human Noxa protein

Supplementary information

This supplementary information is collated from multiple sources and compiled automatically.

Noxa also known as PMAIP1 is a pro-apoptotic member of the Bcl-2 protein family. It has a molecular weight of approximately 20 kDa. Noxa commonly expresses in a number of tissues including lymphoid and myeloid lineages. It functions by interacting with other Bcl-2 family proteins like Mcl-1 promoting apoptosis through binding and neutralization of anti-apoptotic proteins. This interaction facilitates the release of cytochrome c from the mitochondria triggering caspase activation and subsequent apoptosis.

Biological function summary

Noxa plays a role in the regulation of programmed cell death including being part of multiprotein complexes within the mitochondria. Noxa's expression is upregulated in response to various cellular stress signals. These stresses include DNA damage and hypoxia where it acts to mediate apoptosis preventing the survival of cells with potential mutations. Its role in modulating apoptosis makes it key in maintaining cellular homeostasis.

Pathways

Noxa is involved in significant apoptotic and cellular stress response pathways. It forms part of the intrinsic apoptosis pathway which is tightly regulated by Bcl-2 family members like BAK and BAX. Noxa's ability to neutralize Mcl-1 allows the activation of these proteins committing the cell to apoptosis. It also participates in the p53 signaling pathway which is important for the cellular response to DNA damage wherein p53 directly transactivates Noxa.

Noxa is important in cancer and autoimmune syndromes. In cancer its expression often correlates with the sensitivity of cancer cells to chemotherapy as its role in apoptosis can enhance the elimination of cancerous cells. Mutations in p53 that impair its function can lead to decreased Noxa expression and apoptosis contributing to cancer progression. In autoimmune disorders aberrant regulation of apoptosis sometimes involving Noxa and its interaction with Bcl-2 proteins can result in premature cell death or survival of autoreactive cells exacerbating the disease.