Figure 5.

CLK-1(ΔMTS)::GFP cannot rescue the phenotypes of clk-1 mutants (a) clk-1(qm30) mutants grow slowly when fed OP50 and arrest when fed UQ₈-deficient bacteria GD1. Both phenotypes are rescued by a single copy insertion of full length CLK-1::GFP. Neither phenotype is rescued by a single copy insertion of CLK-1(ΔMTS)::GFP, which lacks the mitochondrial targeting sequence of clk-1. (n ≥ 30 animals for each genotype). (b) The slow pumping rate and slow defecation of clk-1(qm30) mutants can be fully rescued by the expression of full length CLK-1::GFP but not by the expression of CLK-1(ΔMTS)::GFP. Bars represent the mean number of pumps per minute or the mean defecation cycle of animals that have been scored for three consecutive defecation cycles each in the case of clk-1(qm30) mutants and for five consecutive defecation cycles for all the other genotypes. The error bars represent S.E.M. (n ≥ 20 animals for each genotype). The asterisks indicate that the data are significantly different from that of the wild-type. All differences were significant at p < 0.0001 by a t-test. (c), (d) and (f) The expression of CLK-1(ΔMTS)::GFP had no effect on the lifespans of clk-1(qm30), clk-1(qm30); daf-2(e1370) or clk-1(e2519) mutants. (e) Treatment with 1 mM 2,4-DHB rescues the lengthened lifespan of clk-1(qm30); CLK-1(ΔMTS)::GFP and has no effect on the lifespan of the wild type. Numerical values and statistical analyses for all lifespan experiments are presented in Table S2.