Figure 6.

Mutations in the eat-6 gene alter tolerance to ethanol-induced hypercontraction. (A) The eg200 mutant animals have decreased movement compared with wild-type animals on ethanol. In these representative illustrations, images of wild-type and eg200 worms were captured every 10 sec over a 2-min period after 30 min of ethanol exposure (400 mM). The progression of time is indicated by darkening worm silhouettes. Bars, 2 mm. (B) Average speeds of wild-type and eg200 mutant animals in the absence and presence of ethanol (400 mM) after 30 min of exposure (***P < 0.001; n = 5). (C) The eat-6(eg200) mutation increases the sensitivity to paralysis caused by prolonged exposure to the AChR agonist, levamisole (100 μM) (**P < 0.01; ***P < 0.001; n = 3). (D) The eg200 mutation was mapped between SNPs on chromosome V and between endpoints of the deletions arDf1 and yDf12. The approximate endpoints of the deletions were determined by placing CB4856-specific SNPs (i–viii) in trans to the deletion-bearing chromosomes and sequencing to determine genotype at each SNP (hemizygous CB4856 or heterozygous N2/CB4856). (E) The eg200 mutation is predicted to cause a substitution of a glutamic acid for a conserved glycine (Gly77) in the EAT-6 protein. The mutation is a G to A substitution in exon 2 of eat-6 (nucleotide 230 of the mRNA sequence; position 13,129,568 of the chromosome V nucleotide sequence).