Worm Breeder's Gazette 11(3): 32
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.
Animals homozygous for certain unc-52 mutations exhibit a progressive paralysis, the onset of which can occur as early as the L3 stage or as late as the mature adult depending on the allele. Examination of body wall muscle in these mutants reveals that paralysis is due to the detachment of the muscle filaments from the outer membrane. Recently, recessive lethal alleles of unc-52 have been identified ( Williams and Waterston, WBG 11(1):45). Hermaphrodites heteroallelic for a non-lethal allele over a lethal allele exhibit the paralyzed phenotype and, in addition, are sterile. The gonad in adult animals is abnormal when viewed by Nomarski optics. Curiously, the same non- lethal allele over a deficiency for the region, jDf4, results in a fertile, paralyzed worm. The unc-52 gene has been cloned by Tc1-tagging, and two non- overlapping, partial cDNAs have been isolated and sequenced. One cDNA contains the Tc1 insertion site, and its deduced 700 a.a. open reading frame shows similarity to the cell adhesion members of the immunoglobulin superfamily. The most striking similarity is with a mouse basement membrane proteoglycan (Noonan et al., J. Biol. Chem. 263:16379-16387, 1988). The second cDNA is approximately 3 Kb upstream from the first and is transcribed in the same direction. This 350 a.a. open reading frame has homology to the laminin B chains, as well as a laminin-like domain of the mouse basement membrane proteoglycan mentioned above. The genomic DNA between these two regions is currently being sequenced to determine if they are both part of unc-52.