Worm Breeder's Gazette 14(1): 73 (October 1, 1995)
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.
|1||The Graduate University for Advanced Studies|
|2||National Institute of Genetics, Mishima, 411, Japan|
We are interested in the functions and genetic interactions of the flr genes, which are defined by fluoride-resistant mutations. They are grouped into two classes by the phenotypes, i.e., class 1 mutants (flr-1, flr-3, flr-4) show slow growth, small blood size and strong resistance to fluoride ion, whereas class 2 mutants (flr-2, flr-5) show normal growth, normal brood size and weak resistance to fluoride ion. Phenotypes of double mutants between the class 1 and class 2 mutations reveal complex and interesting epistasis: they are almost normal in growth and brood size but strongly resistant to fluoride ion (I.Katsura et al. Genetics 136, 145-154 (1994)). The flr mutations also affect neural functions: K.Iwasaki, D.W.C.Liu and J.H.Thomas reported that the class 1 mutants show short defecation cycle periods (Dec-s) (wm95, p286), while we found that some of the flr mutants are defective in chemotaxis (unpublished results) and most of them show synthetic Dauer-constitutive phenotypes (wm95, p303). To elucidate the molecular mechanism of the functions and interactions of the flr gene products, we cloned flr-1 and flr-3 by transposon tagging. flr-1 encodes a degenerin-like ion channel, whereas flr-3 encodes a protein kinase or a kinase-like molecule belonging to a new family (wm95, p304). Furthermore, we recently found that the cosmid F09B12 rescues the slow- growing and Dec-s phenotypes, if it is injected into the gonad of the flr-4(ut7) mutant. A major part of the cosmid has been sequenced already by the genome project. Since it contains an ORF that shows homology to KSS1 protein kinase, we are now testing if subclones containing this ORF can rescue the flr-4 mutation. We expect the studies on the flr genes will reveal a new signal transduction system that affects growth rate and some neural functions in C. elegans.