In
unc-51 mutants, several neurons have abnormally guided axons (HSN, C. Desai et al. Nature. 336 (1988) 638-646; PDE, amphid and phasmid neurons, E. Hedgecock et al. Dev. Biol. 111 (1985) 158-170 etc.). Several unc mutants were found among progenies of mutator strain RW7097. One of them did not complement
unc-51(
e369), and it was tentatively named as UF. UF reverted at a high frequency. These results suggested that UF carried Tc1 insertion in the
unc-51 gene. To analyze the function of
unc-51 gene, we tried to clone this gene with Tc1 probe. To reduce the number of Tc1 copies, UF was crossed with N2 ten times. This strain was named
unc-51(
ks38::Tc1). Southern blot analysis showed that the
unc-51(
ks38::Tc1) contained about ten extra Tc1s when compared with N2. To find a Tc1 which had inserted into the
unc-51 gene, RFLP analysis was done with flanking DNA of extra Tc1s. One clone hybridized with a 4.3kb EcoRI fragment in unc- 51
(ks38::Tc1), but with a 2.7kb EcoRI fragment in revertants and N2. This DNA fragment may contain a part of
unc-51 gene. To map the DNA fragment, we are sending this clone to MRC. If this clone is mapped near the
unc-51 gene, we will try to clone cDNA and to analyze the genomic and cDNA clones.