Worm Breeder's Gazette 2(2): 14
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.
We are characterizing 5 temperature sensitive (ts) fertilization defective mutants. These were isolated as ts steriles which lay unfertilized oocytes at 25 C. They all make normal amounts of sperm and are rescuable by mating with wildtype males, so their defects are in the sperm. The mutant hermaphrodites lay 150-220 unfertilized oocytes at 25 C and a small number (1-6%) of progeny. tsH4 and tsH3 lay a small number of defective zygotes as well. tsH2, tsH3 and tsH4 lay 30-60 unfertilized oocytes and 160-200 progeny at the permissive temperature. Hermaphrodite sperm are swept out of the spermatheca by the oocytes at a rate characteristic of each mutant. The males of the 4 mutants are sterile as well at 25 C as judged by mating them with 25 C grown tsH17 hermaphrodites which do not have any sperm. The male sterility is not due to defective mating because sperm are transferred to the uterus of the mated hermaphrodites. tsH24 males and tsH1 males stimulate oogenesis in the mated hermaphrodites, but tsH2, tsH3 and tsH4 males have so far failed to stimulate oogenesis although sperm are transferred. The temperature sensitive period (TSP) of tsH3, tsH4 and tsH24 has been determined. Although the onset of the TSP varies from 20 to 30 25 C-hours, they all extend throughout spermatogenesis and end at 44- 46 hrs, slightly after egg laying begins. tsH24 recovers fertility when shifted from 25 C to 16 C after spermatogenesis is finished. This suggests that the defective gene product is reversibly temperature sensitive and is in the sperm. The sperm of these mutants are being examined by electron microscopy to detect fine structural alterations and we hope to analyze them biochemically as well.