CD133 Antibody – Rabbit Polyclonal

This gene encodes a pentaspan transmembrane glycoprotein. The protein localizes to membrane protrusions and is often expressed on adult stem cells, where it is thought to function in maintaining stem cell properties by suppressing differentiation. Mutations in this gene have been shown to result in retinitis pigmentosa and Stargardt disease. Expression of this gene is also associated with several types of cancer. This gene is expressed from at least five alternative promoters that are expressed in a tissue-dependent manner. Multiple transcript variants encoding different isoforms have been found for this gene. [provided by RefSeq, Mar 2009]

CD133: Binds cholesterol in cholesterol-containing plasma membrane microdomains. Proposed to play a role in apical plasma membrane organization of epithelial cells. During early retinal development acts as a key regulator of disk morphogenesis. Involved in regulation of MAPK and Akt signaling pathways. In neuroblastoma cells suppresses cell differentiation such as neurite outgrowth in a RET-dependent manner. Interacts with CDHR1 and with actin filaments. Isoform 1 is selectively expressed on CD34 hematopoietic stem and progenitor cells in adult and fetal bone marrow, fetal liver, cord blood and adult peripheral blood. Isoform 1 is not detected on other blood cells. Isoform 1 is also expressed in a number of non-lymphoid tissues including retina, pancreas, placenta, kidney, liver, lung, brain and heart. Found in saliva within small membrane particles. Isoform 2 is predominantly expressed in fetal liver, skeletal muscle, kidney, and heart as well as adult pancreas, kidney, liver, lung, and placenta. Isoform 2 is highly expressed in fetal liver, low in bone marrow, and barely detectable in peripheral blood. Isoform 2 is expressed on hematopoietic stem cells and in epidermal basal cells. Expressed in adult retina by rod and cone photoreceptor cells. Belongs to the prominin family. 7 isoforms of the human protein are produced by alternative splicing.

Protein type: Cell surface; Membrane protein, multi-pass; Membrane protein, integral

Chromosomal Location of Human Ortholog: 4p15.32

Cellular Component: stereocilium; extracellular space; cell surface; photoreceptor outer segment; microvillus membrane; endoplasmic reticulum; integral to plasma membrane; apical plasma membrane; plasma membrane; ER-Golgi intermediate compartment; vesicle; brush border

Molecular Function: actinin binding; protein binding; cadherin binding

Biological Process: photoreceptor cell maintenance; retina morphogenesis in camera-type eye

Disease: Macular Dystrophy, Retinal, 2; Stargardt Disease 4; Retinitis Pigmentosa 41; Cone-rod Dystrophy 12