The myelination of axons in the vertebrate nervous system through oligodendrocytes promotes efficient axonal conduction, which is required for the normal function of neurons. The central nervous system (CNS) can regenerate damaged myelin sheaths through the process of remyelination, but the failure of remyelination causes neurological disorders such as multiple sclerosis. In mammals, parenchymal oligodendrocyte progenitor cells (OPCs) are known to be the principal cell type responsible for remyelination in demyelinating diseases and traumatic injuries to the adult CNS.
View Article and Find Full Text PDFSpinal motor neurons project their axons out of the spinal cord via the motor exit point (MEP) and regulate their target muscle fibers for diverse behaviors. Several populations of glial cells including Schwann cells, MEP glia, and perineurial glia are tightly associated with spinal motor axons in nerve fascicles. Zebrafish have two types of spinal motor neurons, primary motor neurons (PMNs) and secondary motor neurons (SMNs).
View Article and Find Full Text PDFNeuropeptide Y (NPY) is an evolutionarily conserved neuropeptide implicated in feeding regulation in vertebrates. In mammals, NPY neurons coexpress Agouti-related protein (AgRP) in the arcuate nucleus of the hypothalamus, and NPY/AgRP neurons activate orexigenic signaling to increase food intake. Zebrafish express npy and two agrp genes, agrp1 and agrp2, in the brain.
View Article and Find Full Text PDFLIM-homeodomain (HD) transcription factors form a multimeric complex and assign neuronal subtype identities, as demonstrated by the hexameric ISL1-LHX3 complex which gives rise to somatic motor (SM) neurons. However, the roles of combinatorial LIM code in motor neuron diversification and their subsequent differentiation is much less well understood. In the present study, we demonstrate that the ISL1 controls postmitotic cranial branchiomotor (BM) neurons including the positioning of the cell bodies and peripheral axon pathfinding.
View Article and Find Full Text PDFGalanin is a multifunctional neuropeptide that is implicated in the modulation of physiological processes, including nociception, cognition, feeding behavior, neuronal growth, and reproduction. The physiological effects of galanin are mediated through its interaction with three different G protein-coupled receptors, i.e.
View Article and Find Full Text PDFDemyelination is the pathological process by which myelin sheaths are lost from around axons, and is usually caused by a direct insult targeted at the oligodendrocytes in the vertebrate central nervous system (CNS). A demyelinated CNS is usually remyelinated by a population of oligodendrocyte progenitor cells, which are widely distributed throughout the adult CNS. However, myelin disruption and remyelination failure affect the normal function of the nervous system, causing human diseases such as multiple sclerosis.
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