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Rhesus macaque versus rat divergence in the corticospinal projectome.

ABSTRACT: We used viral intersectional tools to map the entire projectome of corticospinal neurons associated with fine distal forelimb control in Fischer 344 rats and rhesus macaques. In rats, we found an extraordinarily diverse set of collateral projections from corticospinal neurons to 23 different brain and spinal regions. Remarkably, the vast weighting of this "motor" projection was to sensory systems in both the brain and spinal cord, confirmed by optogenetic and transsynaptic viral intersectional tools. In contrast, rhesus macaques exhibited far heavier and narrower weighting of corticospinal outputs toward spinal and brainstem motor systems. Thus, corticospinal systems in macaques primarily constitute a final output system for fine motor control, whereas this projection in rats exerts a multi-modal integrative role that accesses far broader CNS regions. Unique structural-functional correlations can be achieved by mapping and quantifying a single neuronal system's total axonal output and its relative weighting across CNS targets.

SUBMITTER: Sinopoulou E

PROVIDER: S-EPMC9509478 | biostudies-literature | 2022 Sep

REPOSITORIES: biostudies-literature

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Rhesus macaque versus rat divergence in the corticospinal projectome.

Sinopoulou Eleni E Rosenzweig Ephron S ES Conner James M JM Gibbs Daniel D Weinholtz Chase A CA Weber Janet L JL Brock John H JH Nout-Lomas Yvette S YS Royz Eric E Takashima Yoshio Y Biane Jeremy S JS Kumamaru Hiromi H Havton Leif A LA Beattie Michael S MS Bresnahan Jacqueline C JC Tuszynski Mark H MH

Neuron 20220801 18

We used viral intersectional tools to map the entire projectome of corticospinal neurons associated with fine distal forelimb control in Fischer 344 rats and rhesus macaques. In rats, we found an extraordinarily diverse set of collateral projections from corticospinal neurons to 23 different brain and spinal regions. Remarkably, the vast weighting of this "motor" projection was to sensory systems in both the brain and spinal cord, confirmed by optogenetic and transsynaptic viral intersectional t ...[more]

PMID: 35917818

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Dataset Information

Rhesus macaque versus rat divergence in the corticospinal projectome.

Publications

Rhesus macaque versus rat divergence in the corticospinal projectome.

Similar Datasets

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