Axon elongation and axon initial segment function

Molecular and Cellular Neurobiology
Instituto Cajal CSIC

The proper function of neuronal physiology, and thus the functions of the nervous system depends on a high degree of morphological and functional polarization. The first step in the morphological polarization of neurons is the formation and growth of an axon to reach their targets, followed by the development of dendrites. The dendrites and axons exhibit differential expression of structural and functional proteins, allowing a vectorial transmission of information between the dendrites and the axon terminals. Accompanying the axonal elongation, it is generated the Axon Initial Segment (AIS), place of action potentials generation in response to signals received by the neuron. This is possible by the high concentration of voltage-gated ion channels in a space of about 35 microns. This action potential is amplified and propagated along the axon at the nodes of Ranvier to reach the pre-synaptic region where neurotransmitters are released. he axon initial segment is extremely important in the neuron, and neuronal physiology depends on proper function. First is where the nerve impulse is generated, and also acts as a barrier that differentiates the somato-dendritic and axonal domains controlling protein trafficking to the axon. Thus, its integrity is necessary for the regeneration of axons after injury. Its dysfunction or composition alteration is related to multiple nervous system diseases (eg, Angelman Syndrome, Alzheimer's, schizophrenia, autism etc. ..), as well as injuries due to traumatic brain damage or ischemia.

The laboratory offers the possibility to carry on a TFM regarding different physiological and pathological aspects related to the Axon Initial Segment. Briefly, the TFM will focus how some neurotransmitter receptors modify AIS protein composition and function, and their possible use as therapeutic targets for brain disorders and neurodegenerative diseases.

Biomolecules & Cell D.
Molecular Biomedicine