mNGF 2.5S-Biotin. A Biotin Labeled�Mouse Nerve Growth Factor
The neurotrophins ("neuro" means nerve and "trophe" means nutrient) are a family of soluble, basic protein growth factors which regulate neuronal development, maintenance, survival and death in the CNS and the PNS. NGF, the first member of the family to be discovered, was originally purified as a factor supporting and regulating survival, development, function and plasticity of sympathetic and sensory spinal neurons in central and peripheral nervous systems
in vivo�as well as�
in vitro.�
It is synthesized and secreted by sympathetic and sensory target organs and provides trophic support to neurons as they reach their final target. Neurotrophin secretion increases in the nervous system following injury. Schwann cells, fibroblasts, and activated mast cells normally synthesize NGF constitutively, however, direct trauma and induction of cytokines combine to increase neurotrophin production in these cells after injury.
NGF is purified in three forms: the 7S, 2.5S and�beta, in which the biologically active subunit is the�beta subunit. The structural hallmark of all the neurotrophins is the characteristic arrangement of the disulfide bridges known as the cysteine knot, which has been found in other growth factors such as Platelet-Derived Growth Factor.
For the past three decades, biotinylated derivatives of NGF are widely used in the literature as useful probes for the study of the binding and the initial intracellular processing of this growth factor by cells bearing TrkA NGF receptor.
First studies using�125I-NGF have visualized the intracellular location of NGF. A biotinylated derivative of NGF that retains biological activity, in conjunction with the appropriate avidin conjugates and fluorescent or confocal microscopic techniques, improve the sensitivity and resolution in many applications.�Some examples of applications are: targeting of liposomes containing biotinylated NGF to cells bearing TrkA NGF receptors; elucidating the kinetics and route of ligand-induced internalization of the p75 receptor through signaling endosomes in cycling and differentiated PC12 cells using�biotinylated derivative of NGF; electrically controlled NGF-Biotin delivery from biotin-doped conductive polymer; studying the retrograde axonal transport mechanism of NGF signals from the axon terminal to the cell body.
Label:�Sulfo-NHS-LC-Biotin (~556 Da) was used for labeling mNGF 2.5S (99%). The extent of labeling is 3 molecules of biotin per one molecule of mNGF 2.5S (99%). The biotin is covalently conjugated to the N-terminus or to lysine residues present in the mNGF 2.5S (99%).
Neurotrophic Factors; Nerve Growth Factors �