Title | Sensory and spinal inhibitory dorsal midline crossing is independent of Robo3. |
Publication Type | Journal Article |
Year of Publication | 2015 |
Authors | Comer JD, Pan FCheng, Willet SG, Haldipur P, Millen KJ, Wright CVE, Kaltschmidt JA |
Journal | Front Neural Circuits |
Volume | 9 |
Pagination | 36 |
Date Published | 2015 |
ISSN | 1662-5110 |
Keywords | Age Factors, Amino Acids, Animals, Axons, Body Patterning, Embryo, Mammalian, Gene Expression Regulation, Developmental, Green Fluorescent Proteins, Membrane Proteins, Mice, Mice, Transgenic, Motor Activity, Mutation, Nerve Tissue Proteins, Neural Cell Adhesion Molecule L1, Neural Inhibition, Nociceptors, Signal Transduction, Spinal Cord, Transcription Factors |
Abstract | Commissural neurons project across the midline at all levels of the central nervous system (CNS), providing bilateral communication critical for the coordination of motor activity and sensory perception. Midline crossing at the spinal ventral midline has been extensively studied and has revealed that multiple developmental lineages contribute to this commissural neuron population. Ventral midline crossing occurs in a manner dependent on Robo3 regulation of Robo/Slit signaling and the ventral commissure is absent in the spinal cord and hindbrain of Robo3 mutants. Midline crossing in the spinal cord is not limited to the ventral midline, however. While prior anatomical studies provide evidence that commissural axons also cross the midline dorsally, little is known of the genetic and molecular properties of dorsally-crossing neurons or of the mechanisms that regulate dorsal midline crossing. In this study, we describe a commissural neuron population that crosses the spinal dorsal midline during the last quarter of embryogenesis in discrete fiber bundles present throughout the rostrocaudal extent of the spinal cord. Using immunohistochemistry, neurotracing, and mouse genetics, we show that this commissural neuron population includes spinal inhibitory neurons and sensory nociceptors. While the floor plate and roof plate are dispensable for dorsal midline crossing, we show that this population depends on Robo/Slit signaling yet crosses the dorsal midline in a Robo3-independent manner. The dorsally-crossing commissural neuron population we describe suggests a substrate circuitry for pain processing in the dorsal spinal cord. |
DOI | 10.3389/fncir.2015.00036 |
Alternate Journal | Front Neural Circuits |
PubMed ID | 26257608 |
PubMed Central ID | PMC4511845 |
Grant List | P60 DK020593 / DK / NIDDK NIH HHS / United States R01 NS083998 / NS / NINDS NIH HHS / United States U19 DK042502 / DK / NIDDK NIH HHS / United States DK58404 / DK / NIDDK NIH HHS / United States P30 DK058404 / DK / NIDDK NIH HHS / United States NS083998 / NS / NINDS NIH HHS / United States U01 DK089570 / DK / NIDDK NIH HHS / United States T32GM007739 / GM / NIGMS NIH HHS / United States P30 CA008748 / CA / NCI NIH HHS / United States DK59637 / DK / NIDDK NIH HHS / United States P30 DK020593 / DK / NIDDK NIH HHS / United States P30 CA068485 / CA / NCI NIH HHS / United States DK089570 / DK / NIDDK NIH HHS / United States CA68485 / CA / NCI NIH HHS / United States T32 GM007739 / GM / NIGMS NIH HHS / United States DK42502 / DK / NIDDK NIH HHS / United States DK20593 / DK / NIDDK NIH HHS / United States P01 DK042502 / DK / NIDDK NIH HHS / United States R01 NS072441 / NS / NINDS NIH HHS / United States U24 DK059637 / DK / NIDDK NIH HHS / United States |
Submitted by kej2006 on June 6, 2018 - 4:11pm