Table 2.

Single-cell transcriptomic data from four L1 and four L2 neurons

Gene	Protein encoded	L1	L1	L1	L1	L2	L2	L2	L2
Cacna1h	Cav3.2	0	0	0	0	2.8	45	319	47
Kcna2	Kv1.2	320	301	86	206	223	627	1,270	641
Kcna1	Kv1.1	609	313	391	184	279	593	981	1,115
Kcnc4	Kv3.4	19	0	95	56.8	785	383	562	925
Pvalb	Parvalbumin	253	555	257	212	0	0	0	0
Nefh	Neurofilament heavy polypeptide	1,410	1,460	1,111	991	236	312	1,005	826
Ntrk2	Neurotrophic Receptor Tyrosine Kinase 2	0	0	0	1	752	511	1,619	818
Calca	CGRP (α)	1.5	30	3.5	8.6	0	1,080	0	0
Mrgprd	MAS Related GPR Family Member D	0	0	0	0	0	0	0	0
Trpa1	Transient receptor potential ankyrin 1	0	0	0	0	0	0	0	0
Trpm8	Transient receptor potential melastatin 8	0	0	0	0	0	0	0	0
Trpv1	Transient receptor potential vanilloid 1	0	0	0	0	0	0	0	0
Kcna6	Kv1.6	1.0	0	56	25	0	4.9	0	1
Adam22	Disintegrin and Metalloproteinase Domain-Containing Protein 22	148	54	133	58	140	254	53	114
Nrg1	Neuregulin 1	80	1,170	229	134	170	74	26	371

Single-cell transcriptomic data from L1 and L2 neurons. Four cells per subclass are tabulated. Counts are reported in transcripts per million. Similarities and diversities in the expression of select genes are displayed. Both L1 and L2 neurons express Kcna1 and Kcna2 (transcripts encoding for Kv1.1 and 1.2), showing the presence of the RIIIJ target. L1 neurons express high levels of Pvalb, which is considered a marker for proprioceptors and is consistent with differential Ca²⁺ buffering in L1 neurons. Adam22, Nefh, and Nrg1 transcripts were detected in both L1 and L2 neurons as myelination markers. Cacna1h and Ntrk2 are expressed in L2 but not L1 neurons, indicating that L2 neurons are Aδ-LTMRs. Mrgprd (indicative of nonpeptidergic nociceptors), Trpa1, Trpm8, and Trpv1 transcripts were not detected in L1 or L2 neurons. Boldface type identifies genes discussed in the text for ease of reading the table and does not denote particular importance.