Worm Breeder's Gazette 11(1): 55

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.

The unc-60 Story: Chapter 1

Marcia F. Wakarchuk and David L. Baillie

The muscle gene, unc-60, is located on the left end of LGV.  
Homozygous mutants are paralyzed.  The organization of muscle thin 
filaments in mutants is disrupted and results in bunches of thin 
filaments in the corners of muscle cells (Waterston, 1980).  We have 
more than 10 alleles of unc-60, all of which are hypomorphs.  Most 
alleles are dystrophic but two alleles r398 and s1307 show 
antidystrophic properties.  The genetic organization of the unc-60 
region has been done (McKim, 1988).  My project has been to continue 
the molecular and genetic characterization of the unc-60 gene.  In an 
attempt to generate internal deletions of unc-60, I performed two 
mutagenesis experiments using formaldehyde and gamma rays.  The strain 
dpy-18/eT1 III unc-60(s1331); +/eT1 V let-?(s2165) was constructed to 
allow for screening of new mutagen induced unc-60 alleles by 
precomplementation.  Two of the formaldehyde induced mutations, s1980 
and s1981 are deficiencies that delete unc-60 and regions around it.  
The other formaldehyde mutation, s1983 appears to be a point mutation 
of unc-60.  The single gamma allele, s1986 also appears to be a 
deficiency, possibly an intragenic one.  I am planning to map the 
deficiency breakpoints and to investigate the molecular nature of 
these and the unc-60 alleles.  I also performed microinjections of 
cosmid DNA into unc-60(m35) homozygotes.  The cosmids came from the 
contig containing the ges-1 gene (supplied by John and Alan at MRC).  
I achieved transient rescue of unc-60 with the three overlapping 
cosmids (injected together): F53E2, K06H5, and T28A3.  I then injected 
these cosmids singly and achieved rescue with F53E2.  Therefore I 
assume that the coding region of unc-60 lies within the cosmid F53E2.  
At this point, I am not sure if the other two cosmids contain all or 
parts of the unc-60 gene.  I am presently isolating the coding region 
of the gene and will continue to characterize the gene.  I hope to 
also rescue neighboring LGV lethals by microinjection as a 
continuation of our laboratory's goal to study genome organization.  
This work was supported by an SFU Graduate Fellowship to MFW and by 
the Muscular Dystrophy Association of Canada and the Natural Sciences 
and Engineering Council of Canada to DLB.