Figure 5
nlf-1 acts in head acetylcholine neurons to control locomotion. (A)
nlf-1 is expressed widely in the nervous system. A fusion of the
nlf-1promoter to GFP (transgene oxEx1144) is expressed throughout the nervous system. No expression is seen in nonneuronal tissues. An L1 stage larvalanimal is shown with its head to the left. (B and C) The
nlf-1 cDNA was expressed in an
nlf-1(
ox327) mutant background using the following promoters:
rab-3 (all neurons, oxEx1146 transgene),
unc-17 (acetylcholine neurons, oxEx1149 transgene),
unc-17H (a derivative of the
unc-17 promoter that lacksthe enhancer for ventral cord expression and thus expresses in head acetylcholine neurons and occasionally a few tail neurons, oxEx1155 transgene),
unc-17b (a derivative of the
unc-17 promoter that expresses only in ventral cord acetylcholine neurons, oxEx1323 transgene),
acr-2 (ventral cordacetylcholine motor neurons, oxEx1151 transgene), and
glr-1 (interneurons including premotor command interneurons, oxEx1152 transgene). (B)Expression driven by the
rab-3,
unc-17, and
unc-17H promoters rescued the fainting phenotype of an
nlf-1 mutant in the backward direction.***P , 0.001, Dunn's test. Error bars = SEM; n = 15. (C) Expression driven by the
glr-1 promoter partially rescued the fainting phenotype of an
nlf1 mutant in either the backward or forward direction, though the effect was not statistically significant (ns, P . 0.05, two-tailed Mann-Whitney tests;Error bars = SEM, n = 25). However, assays of this strain were complicated by slow movement and frequent pauses that were hard to distinguish fromtrue fainting behavior (see text for details). ns, not significant; WT, wild-type.