Worm Breeder's Gazette 1(1): 16
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.
A Zeiss universal microscope with Nomarski optics has been modified by the addition of a semi-silvered mirror mounted behind the objective. A dye laser giving 0.25 joule pulses at 450 nm wavelength is set up so that the beam is brought into focus in the plane of the object. A spot size of about 1.5 m is produced and this can be used to kill individual cells in the nematode with no apparent damage to their neighbors. It has been found that there is very little regulation of the nematode. When one of the precursors that migrate into the ventral cord is killed, the adjacent ones go through their normal sequence of divisions. The daughters of the precursor that migrates into the RVG behave differently from those in the rest of the cord. When this precursor is killed the next one along will go into the RVG. We are at the moment performing an E/M autopsy on one of these animals to see whether the daughter cells from this precursor behave as the original one would have done or as those from a normal cord precursor. When the mesodermal blast cell of the hermaphrodite is killed a perfectly normal looking animal is produced which is lacking in all the cells which derive from that cell. It cannot lay eggs however, as it has no vulval muscles. When the gonad primordium is killed in the hermaphrodite there is no gonad or vulva produced but the vulval muscles migrate to the right place and start twitching even though there is nothing there.