Neurite
Encyclopedia
A neurite refers to any projection from the cell body of a neuron
. This projection can be either an axon
or a dendrite
. The term is frequently used when speaking of immature or developing neurons, especially of cells in culture
, because it can be difficult to tell axons from dendrites before differentiation
is complete.
Neurites are often packed with microtubule
bundles, the growth of which is stimulated by Nerve Growth Factor
(NGF), as well as tau proteins, MAP1, and MAP2
.
The neural cell adhesion molecule
N-CAM simultaneously combines with another N-CAM and a fibroblast growth factor receptor
to stimulate the tyrosine kinase
activity of that receptor to induce the growth of neurites.
There are several software kits available to facilitate neurite tracing in images (see external links).
Weak endogeneous electric fields may be used to both facilitate and direct the growth of projections from cell soma neurites, EFs of moderate strength have been used to direct and enhance neurite outgrowth in both murine and xenopus models. Co-culture of neurons with electrically alligned glial tissue also directs neurite outgrowth, as it is rich in neurotrophins that promote nerve growth.
Neuron
A neuron is an electrically excitable cell that processes and transmits information by electrical and chemical signaling. Chemical signaling occurs via synapses, specialized connections with other cells. Neurons connect to each other to form networks. Neurons are the core components of the nervous...
. This projection can be either an axon
Axon
An axon is a long, slender projection of a nerve cell, or neuron, that conducts electrical impulses away from the neuron's cell body or soma....
or a dendrite
Dendrite
Dendrites are the branched projections of a neuron that act to conduct the electrochemical stimulation received from other neural cells to the cell body, or soma, of the neuron from which the dendrites project...
. The term is frequently used when speaking of immature or developing neurons, especially of cells in culture
Cell culture
Cell culture is the complex process by which cells are grown under controlled conditions. In practice, the term "cell culture" has come to refer to the culturing of cells derived from singlecellular eukaryotes, especially animal cells. However, there are also cultures of plants, fungi and microbes,...
, because it can be difficult to tell axons from dendrites before differentiation
Cellular differentiation
In developmental biology, cellular differentiation is the process by which a less specialized cell becomes a more specialized cell type. Differentiation occurs numerous times during the development of a multicellular organism as the organism changes from a simple zygote to a complex system of...
is complete.
Neurites are often packed with microtubule
Microtubule
Microtubules are a component of the cytoskeleton. These rope-like polymers of tubulin can grow as long as 25 micrometers and are highly dynamic. The outer diameter of microtubule is about 25 nm. Microtubules are important for maintaining cell structure, providing platforms for intracellular...
bundles, the growth of which is stimulated by Nerve Growth Factor
Nerve growth factor
Nerve growth factor is a small secreted protein that is important for the growth, maintenance, and survival of certain target neurons . It also functions as a signaling molecule. It is perhaps the prototypical growth factor, in that it is one of the first to be described...
(NGF), as well as tau proteins, MAP1, and MAP2
MAP2
Microtubule-associated protein 2 is a protein that in humans is encoded by the MAP2 gene.-Interactions:MAP2 has been shown to interact with Grb2, NEFL and MYO7A.. MAP2 is suspected of interacting with tubulin.-Further reading:...
.
The neural cell adhesion molecule
Neural Cell Adhesion Molecule
Neural Cell Adhesion Molecule is a homophilic binding glycoprotein expressed on the surface of neurons, glia, skeletal muscle and natural killer cells...
N-CAM simultaneously combines with another N-CAM and a fibroblast growth factor receptor
Fibroblast growth factor receptor
The fibroblast growth factor receptors are, as their name implies, receptors that bind to members of the fibroblast growth factor family of proteins. Some of these receptors are involved in pathological conditions...
to stimulate the tyrosine kinase
Tyrosine kinase
A tyrosine kinase is an enzyme that can transfer a phosphate group from ATP to a protein in a cell. It functions as an "on" or "off" switch in many cellular functions....
activity of that receptor to induce the growth of neurites.
There are several software kits available to facilitate neurite tracing in images (see external links).
Weak endogeneous electric fields may be used to both facilitate and direct the growth of projections from cell soma neurites, EFs of moderate strength have been used to direct and enhance neurite outgrowth in both murine and xenopus models. Co-culture of neurons with electrically alligned glial tissue also directs neurite outgrowth, as it is rich in neurotrophins that promote nerve growth.