Worm Breeder's Gazette 9(1): 52
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.
At the last C. elegans meeting, we reported that rabbit antibodies prepared against adult cuticle proteins bind to the surface of live adults and can be rendered adult-specific (free of L4-cross-reacting antibodies) by pre-adsorption with saturating numbers of live L4's. These antibodies were elicited by an immunogen mixture derived from the N2(Bristol) strain. We have tested twelve different C. elegans strains for the presence of the adult-specific antigen class recognized on the N2 surface. For immunofluorescence staining of each strain, approximately 150 worms of mixed stages were incubated with an amount of adult-specific antibody sufficient to saturate binding of 150 N2 adults. After a second incubation with FITC second antibody, worms were spread onto 2% agarose-0.9% NaCl plates and viewed under a dissecting microscope equipped with FITC optics. The number of fluorescent vs non-fluorescent adults was scored; no larvae were observed to fluoresce. Each strain showed a characteristic fraction of antigen-positive (srf+) individuals. While N2, as expected, scored highest (>95% srf+ adults), and eight other strains (PA-2, GA-1, GA-2, AB-1, CL-2A, GA-S, AB-3, and Bergerac FR) could be characterized as 'intermediate' (>40% srf+ adults), three strains (PA-1, DH424, and Bergerac BO) were essentially antigen-negative (<5% srf+ adults). Because the phenotypic difference between N2 and PA-1, DH424, or Bergerac BO is clearcut, we are analyzing the genetic differences that account for the observed surface antigenic differences by crossing N2 marked hermaphrodites with PA-1 or DH424 males. So far, in such a cross between unc-4(e120) and PA-1 we have shown that the antigen- negative phenotype is dominant in the F1; i.e., F1 selfs are srf+, but F1 outcross are srf-.