Table 1.

NsERK2 KO versus ERK2^f/f (control)^a

	ERK2f/f	NsERK2 KO	p
Total neurons	9879 ± 724 (4)	9190 ± 316 (4)	0.4167
CGRP (%)	33.11 ± 4.45% (6)	27.71 ± 3.12% (6)	0.3442
TrkA (%)	26.17 ± 2.65% (5)	23.90 ± 2.71% (6)	0.5680
IB4+ (%)	14.89 ± 1.76% (4)	14.71 ± 1.24% (4)	0.9384
NF200+ (%)	31.36 ± 5.58%b (3)	31.97 ± 3.78% (4)	0.8131

^a Neither ERK2 nor ERK1 alone is necessary for survival and normal distribution of DRG neuron subpopulations. Data are DRG neuron distributions in NsERK2 KO compared with the distributions in control littermates. Total neuron data represent total neuron counts in L5 DRGs. For specific markers, the percentage of marker-specific positive neurons is reported as measured in one ganglion from L3-L5 DRGs. Data represent mean ± SEM; values in parentheses are the number of animals for each experiment.

^b The same control (ERK2^f/f) used for NsERK2 KO and ERK1 KO littermates from ERK dKO colony.