Worm Breeder's Gazette 10(1): 97
These abstracts should not be cited in bibliographies. Material contained herein should be treated as personal communication and should be cited as such only with the consent of the author.
Hermaphrodites homozygous for the unc-23(e324)V mutation have dystrophic heads that are dragged or pushed along as they move forward. The hermaphrodites also appear to be slightly egg-laying deficient. This marker is very useful for genetic mapping and we mapped ama-2( m323), which confers dominant resistance to the fungal toxin alpha- amanitin, relative to unc-23 in a two-factor cross. unc-23 progeny of unc-23 +/+ ama-2 heterozygotes were placed singly into microtiter wells containing alpha-amanitin in a suspension of OP50 in S medium. Resistant hermaphrodites that resulted from recombination between unc- 23 and ama-2 produced progeny that grew to adulthood. When the progeny that grew in alpha-amanitin were put onto plates, we noticed a curious phenomenon. Only about one-fourth of the resistant progeny displayed the unc-23 phenotype; three-fourths appeared wild-type (i.e., they no longer dragged their heads). After 24 to 48 hours on plates, some of those that initially appeared to be wild-type dragged their heads, but the rest continued to appear wild-type. Several of these persistently 'wild-type' hermaphrodites were cloned on plates and all of their progeny exhibited the unc-23 phenotype (they dragged their heads). These observations lead us to conclude that growth in liquid 'cures' the unc-23 phenotype at least 50% of the time. This phenomenon may have been observed by others in the past, but we haven't heard of it. It may be the first successful application of hydrotherapy in C. elegans.Incidentally, the ama-2 gene was ultimately positioned between the right end of ctDf1 and unc-76.