We have taken a genetic approach to identify molecules involved in neurotransmission. We identified several previously unidentified genes in a behavioral screen for mutants defective in synaptic function. Among these was
ric-5(
n1337). When touched on the head,
ric-5(
n1337) mutants move backwards in a jerky, uncoordinated fashion, and frequently coil.
ric-5 maps to the cluster of LG III. To obtain putative null alleles of
ric-5, a noncomplementation screen was conducted to generate additional alleles. Approximately 7000 EMS mutagenized genomes were screened, and we recovered 7 new alleles of
ric-5. We mapped the position of
ric-5 to the right of
mec-14 and to the left of
lin-39. Several other mutations resembling the
ric-5 phenotype mapped to this same region.
osm-13(
n1602) (Josh Kaplan and Anne Hart, personal communication) mapped to this interval and we demonstrated that
n1337 and
n1602 failed to complement. Carl Johnson mapped
ric-1(
e239) to this interval, and we demonstrated that
e239 and
n1337 failed to complement. In light of these data,
ric-5 has now been renamed
ric-1. Jim Rand's laboratory has isolated 19 mutations in
ric-1, bringing the total number of
ric-1 alleles to 28. Microinjection of cosmid pools spanning this region weakly rescue the coiling phenotype of
ric-1.