nca(gf) exhibit exaggerated body bends during movements, resulting in periodic coiling ( Yeh et al., 2008). nca(gf);nlf-1 mutants exhibit movements in normal body bends and do not coil (data not shown). Our qualitative and quantitative behavioral analyses placed nlf-1 in the same genetic pathway as the nca genes. The locomotion deficit of nca(lf), unc-79 and unc-80 null mutants, referred to as fainters henceforth, is unique. The hallmark feature of fainter is the frequent halting during an otherwise grossly normal motor pattern, led by a relaxation of its anterior region that selleck screening library prevents body bend initiation and propagation ( Figure 1A, top panels, denoted by asterisks). Qualitatively, both null allele

nlf-1 mutants (see below) exhibit characteristic fainter movements with frequent, brief halting, accompanied by a relaxed anterior body posture unique for fainters ( Figure 1A; Movie S1B). They do not exhibit additional phenotypes from nca(lf) (Movies S1A and S1B). We can describe fainter’s motor deficit by two quantifiable parameters generated by automated behavioral analyses: relative idle/active states (Figure 1D) and rhythmicity in the motor pattern (Figures 1B and 1C). For idle/active states, we quantify the percentage of time that animals move and pause. An instantaneous speed of the centroid movement equal to/higher and less than 1 pixel/second is defined as movement

and pausing, respectively (Experimental Procedures; Kawano et al., 2011). On our standard

culture plates, while wild-type (N2) animals seldom stayed idle, the frequent halting by nca(lf) fainters led to a significantly Y-27632 cost increased fraction of the idle state ( Figure 1D). For rhythmicity, we quantify the curvature of the anterior region during crawling ( Figure 1A, bottom panels, denoted by a black asterisk and dashed line). Wild-type animals generated continuous and rhythmic sinusoidal body bending that propagated either posteriorly or anteriorly ( Figure 1A, lower panels; Pierce-Shimomura et al., 2008). nca(lf) fainters Ketanserin exhibited discontinuous bending patterns ( Figure 1A, lower panels), reflected by a drastic reduction of the bending curvature in the anterior body ( Figure 1B, denoted by arrow heads; Figure 3A) that resulted in a significant reduction in body bending frequency ( Figure 1C). Like nca(lf), nlf-1 mutants showed an increased propensity for idle state ( Figure 1D), a significantly reduced anterior bending curvatures ( Figure 1B), and a reduced frequency of body bending initiation ( Figure 1C). Both alleles exhibited similar degree of motor deficits ( Figures 1A–1D). In all parameters, nlf-1 mutants consistently exhibited slightly less severe phenotypes than nca(lf) ( Figures 1B–1D). Critically, nlf-1;nca(lf) animals phenocopied nca(lf) in all parameters ( Figures 1B–1D), and showed no additional phenotype from nca(lf) (Movies S1C and S1D).