Higher primate-like direct corticomotoneuronal connections are transiently formed in a juvenile subprimate mammal.

ABSTRACT: The corticospinal (CS) tract emerged and evolved in mammals, and is essentially involved in voluntary movement. Over its phylogenesis, CS innervation gradually invaded to the ventral spinal cord, eventually making direct connections with spinal motoneurons (MNs) in higher primates. Despite its importance, our knowledge of the origin of the direct CS-MN connections is limited; in fact, there is controversy as to whether these connections occur in subprimate mammals, such as rodents. Here we studied the retrograde transsynaptic connection between cortical neurons and MNs in mice by labeling the cells with recombinant rabies virus. On postnatal day 14 (P14), we found that CS neurons make direct connections with cervical MNs innervating the forearm muscles. Direct connections were also detecte

SUBMITTER: Murabe N 

PROVIDER: S-EPMC6224497 | biostudies-literature | 2018 Nov

REPOSITORIES: biostudies-literature