NEURONAL ORDERING IN A SIMPLE NUCLEUS

Project: Research project

Description

A major problem in developmental neurobiology involves determining the
rules underlying axonal guidance and the establishment of neuronal order
within the vertebrate brain. The failure of neurons to establish the
proper connections or the proper type of connections win generally result
in sensory or motor deficits. Rules underlying neuronal ordering vary
across systems and within a system across species. For this reason,
several workers have proposed investigating new models, to separate general
principles from systems-specific variations. The goal of the research
proposed here is to develop a new model system, the first order
electrosensory nucleus (nE) of teleost fishes, for examining the principles
of ordering within vertebrates. The nE is a monosensory preparation
exhibiting the following features: somatotopic organization, simplicity
(only two major cell types that are arranged into discrete laminae),
experimental accessibility to its afferent neurons, and, across species,
the presence of either a one-map or a four-map nucleus. Immunocytochemical
and tract-tracing techniques will be combined to explore six questions
concerning the formation of the nE: 1) Where along the neural axis do nE
cells arise?; 2) How do the two cell types -- granular and pyramidal cells
-- sort themselves into laminae?; 3) Can primary afferents play a role in
establishing nE somatotopy?; 4) Does cell death occur?; 5) Do established
connections shift target cells with growth?; and 6) How are the one-map and
four-map nuclei developmentally related? These results will be interpreted
within the context of known models of vertebrate neuronal development.
StatusFinished
Effective start/end date6/1/925/31/95

Funding

  • National Institutes of Health: $93,820.00

Fingerprint

Vertebrates
Afferent Neurons
Neurobiology
Pyramidal Cells
Fishes
Cell Death
Neurons
Brain
Growth
Axon Guidance

ASJC

  • Medicine(all)
  • Neuroscience(all)