Neurons Generated In The Adult Brain Learn To Respond To Novel Stimuli

Neurons Generated In The Adult Brain Learn To Respond To Novel Stimuli: "New brain cells that develop in the olfactory system of adult mice appear to play a role in the brain different from that of older neurons. The new olfactory neurons are especially sensitive to novel stimuli, preferentially learning to respond to new odors. This level of flexibility suggests that such newly-generated neurons could be induced to adapt to and integrate into other regions of the brain, perhaps allowing them to replace neurons lost to injury or disease. The report from researchers at the Massachusetts General Hospital (MGH)-Harvard Medical School (HMS) Center for Nervous System Repair (CNSR) appears in the Nov. 16 Journal of Neuroscience."

RNA Splicing Occurs in Nerve-Cell Dendrites

UPHS News: RNA Splicing Occurs in Nerve-Cell Dendrites: "Dendrites, which branch from the cell body of the neuron, play a key role in the communication between cells of the nervous system, allowing for many neurons to connect with each other to form a network. Dendrites detect the electrical and chemical signals transmitted to the neuron by the axons of other neurons. The synapse is the neuronal structure where this chemical connection is formed, and investigators surmise that the synapse is where learning and memory occur."

synapse formation

Scientists Visualize Key Molecular Interactions That Activate The Immune Response To Foreign Proteins: "Using their system, the researchers now can dissect the requirements for synapse formation. Many different membrane proteins are likely to have unique roles in this process. In addition, the biophysical rules that guide each protein also can be uncovered. Therefore, this work has the potential to uncover new factors involved in T cell activation, possibly leading to novel drugs for treating autoimmune diseases, organ transplant rejection, AIDS or cancer. "

Neural Stem Cells and Glial Progenitor Cells

MEDICAL BIOLOGY: NEURAL STEM CELLS AND THE ORIGIN OF GLIOMAS: "It is now known that there are both neural stem cells and glial progenitor cells in multiple regions of the adult brain. Neural stem cells, which are multipotent and self-renewing, have been isolated from the subventricular zone, the lining of the lateral ventricles, the dentate gyrus, within the hippocampus, and the subcortical white matter. The largest of these germinal regions in humans, the subventricular zone, contains a population of astrocytes that can function as neural stem cells. In other adult mammals, glial progenitor cells -- self-renewing precursors capable of producing astrocytes and oligodendrocytes -- have also been observed throughout the neuraxis, including the cortex, the corpus callosum, the periventricular white matter, the subventricular zone, and the dentate gyrus. These stem-cell and progenitor elements, in addition to differentiated adult glia, constitute a substrate for neoplastic transformation."

Hox Genes Code for Motor Neuron Wiring

Hox Code for Motor Neuron Wiring: "Earlier work performed by Dasen and Jessell, in collaboration with Jeh-Ping Liu, who is now at the University of Virginia, established that certain Hox proteins control the differentiation of motor neurons into columns in the spinal cord. These columns, which are arrayed along the anterior-posterior length of the spinal cord, form in the initial phases of motor neuron organization. That organization determines whether motor neurons grow to the limbs or to other targets.

According to Jessell, members of the Hox gene family had been known to regulate aspects of brain development, but "few people had paid attention to the fact that these genes are also expressed in the spinal cord." Earlier work performed by Dasen and Jessell, in collaboration with Jeh-Ping Liu, who is now at the University of Virginia, established that certain Hox proteins control the differentiation of motor neurons into columns in the spinal cord. These columns, which are arrayed along the anterior-posterior length of the spinal cord, form in the initial phases of motor neuron organization. That organization determines whether motor neurons grow to the limbs or to other targets. "