Identify a panel of transcripts that exhibited differential expression between spinal cord motor neurons (spMNs) with low and high regenerative abilities

The mammalian neurons in the central nervous system (CNS) fail to regenerate their axons after injury, while the adult peripheral nervous system (PNS) neurons can regenerate their axons robustly. Promoting the intrinsic regenerative capacity of CNS neurons after injury is potential way to solve this difficulty. For this purpose, we have identified a panel of transcripts that exhibited differential expression between spinal cord motor neurons (spMNs) with low and high regenerative abilities by using retrograde tracing and single-cell RNA sequencing. We classified spinal cord MNs with different regeneration abilities into two groups by labeling their injured axon terminals at the proximal and distal sites of the sciatic nerve with retrograde labeling dyes. That is, fast DIO (Green), which can retrograde diffuse to the soma of spMNs through the injured axonal cell membrane, was injected at the proximal site on the day of operation (Day 0) and labeled all the injured spMNs. Two days after injury (Day 2), we injected fast DiI (Red) into the distal site of the sciatic nerve to mark those spinal cord MNs, whose regenerated axons reached the distal site firstly.