⽇時:2019年8⽉19⽇(⽉)17:00-18:00 場所:総合研究棟1階105号室 対象:どなたでも参加可能です 演者:伊藤 靖浩 先⽣ Research Associate Department of Stem Cell and Regenerative Biology, and Center for Brain Science, Harvard University, Cambridge, MA, USA
講演タイトル: Molecular investigation of corticospinal neuron axonal projection and branching at specific spinal segments (⽇本語でのプレゼンテーションになります)
要旨: Corticospinal neurons (CSN, and related cortico-brainstem neurons; together “CSN”) are located in layer V of the neocortex, and make synaptic connections with circuitry in the spinal cord and brainstem. CSN axons form the corticospinal tract (CST), the major motor output pathway from the cerebral cortex, essential for voluntary motor control. CSN are also clinically important. CSN degeneration in amyotrophic lateral sclerosis (ALS), along with degeneration of spinal motor neurons, causes spasticity and paralysis. In humans, damage to the CST following spinal cord injury is the principal cause of loss of voluntary motor control. Previous studies in our lab have identified combinatorial molecular controls over the specification and differentiation of CSN (1, 2). CSN exhibit striking anatomical and functional diversity: some CSN extend axons to targets in the brainstem and cervical spinal cord (i.e. bulbar-cervical targets; referred to here as CSNBC), while others extend axons to thoraco-lumbar segments (CSNTL). CSNBC control face and arm movement, while CSNTL control trunk and hindlimb movement. We are investigating molecular mechanisms regulating CSN subpopulation-specific axonal projection and spinal segmental connectivity in mice. Furthermore, by using a novel approach our lab recently developed (3), we are investigating subcellular local transcriptomes of CSN growth cones, the tips of growing axons, during mouse CST development.
Reference: 1. Arlotta P*, Molyneaux BJ* et al., Neuronal subtype-specific genes that control corticospinal motor neuron development in vivo, Neuron, 2005 2. Greig LC*, Woodworth MB* et al., Molecular logic of neocortical projection neuron specification, development and diversity, Nat Rev Neurosci, 2013 3. Poulopoulos A*, Murphy AJ* et al., Subcellular transcriptomes and proteomes of developing axon projections in the cerebral cortex, Nature, 2019