Anti-NUMB Antibody Picoband®

Protein numb homolog is a protein that in humans is encoded by the NUMB gene. It is mapped to 14q24.2 to q24.3. The encoded protein, whose degradation is induced in a proteasome-dependent manner by MDM2, is a membrane-bound protein that has been shown to associate with EPS15, LNX1, and NOTCH1. The primary function of Numb in cell differentiation is as an inhibitor of Notch signaling which is essential for maintaining self-renewal potential in stem and progenitor cells. Numb also plays a crucial role in asymmetrical cell division during development, allowing for differential cell fate specification in the central and peripheral nervous systems. What’s more, the numb gene protein product controls binary cell fate decisions in the peripheral and central nervous systems of both invertebrates and mammals during neurogenesis.

The expression of isoforms 1 and 2 does not seem to overlap. Isoform 1 is expressed by the blood vessels of different tissues. In the developing embryo it is found predominantly in the nervous system. In adult tissues, it is highly expressed in heart and placenta; moderately in lung, liver, skeletal muscle, kidney and pancreas; and low in adult brain. Isoform 2 is found in liver hepatocytes, kidney distal and proximal tubules.

Plays a role in the process of neurogenesis. Required throughout embryonic neurogenesis to maintain neural progenitor cells, also called radial glial cells (RGCs), by allowing their daughter cells to choose progenitor over neuronal cell fate. Not required for the proliferation of neural progenitor cells before the onset of neurogenesis. Also involved postnatally in the subventricular zone (SVZ) neurogenesis by regulating SVZ neuroblasts survival and ependymal wall integrity. May also mediate local repair of brain ventricular wall damage.

1. Dho SE, French MB, Woods SA, McGlade CJ (November 1999) . Characterization of four mammalian numb protein isoforms. Identification of cytoplasmic and membrane-associated variants of the phosphotyrosine binding domain. J. Biol. Chem. 274 (46) : 33097–104. 2. Katoh M, Katoh M (September 2006) . NUMB is a break of WNT-Notch signaling cycle. Int. J. Mol. Med. 18 (3) : 517–21. 3. Pece S, Confalonieri S, R Romano P, Di Fiore PP (January 2011) . NUMB-ing down cancer by more than just a NOTCH. Biochim. Biophys. Acta 1815 (1) : 26–43.

Store at -20°C for one year from date of receipt. After reconstitution, at 4°C for one month. It can also be aliquotted and stored frozen at -20°C for six months. Avoid repeated freeze-thaw cycles.