Worm Breeder's Gazette 9(1): 87
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.
Inspired by a lunchtime conversation with Sam Ward and Tabitha Doniach, we decided to attempt artificial insemination of worms by injection of sperm. The recipient animals were females of genotype fog-1(e1959) 7) (from a balanced strain provided by T. Doniach; fog - 'Feminization Of Germline'). Any progeny from these animals indicates successful insemination; the progeny should be non-Unc and half should be male (if sperm from XO parents are used). The sperm donors were males from the strain mab-3(e1240); 67), which were used because they conveniently accumulate large quantities of sperm, due to their complete inability to mate (Hodgkin, 1983). We used the current MRC injection procedure, immobilizing the males and females under oil on a dried agarose pad. The males were ruptured at their tails by poking with the needle, allowing their sperm to flow out. The sperm were then collected by suction from the needle, which had to be rather blunt (large enough to accommodate the sperm). The sperm were then injected through the vulvas of recipient females. Unfortunately, it was difficult to count (or even confirm the presence of) injected sperm using our injection optics. In several experiments, we injected a total of 21 Fog males, which had been verified as lacking fertilized eggs. A total of 9 animals were fertile, most with 1 to 5 progeny, and one parent having 18 progeny (10 hermaphrodite and 8 male) . We confirmed that the F1 hermaphrodites segregated Fog Unc, Him, and wild-type progeny. We have not yet optimized the conditions for this procedure, but it seems clear that it works. The efficiency of insemination must be fairly high, since few sperm are injected into each animal. This procedure should be useful for certain genetic constructs, and for testing the sperm found in mutants that are unable to mate. From these experiments, we can already conclude that mab-3 males have functional sperm.