Worm Breeder's Gazette 4(1): 28

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 Second Acetylcholinesterase Mutant of C. elegans

J. Culotti, G. von Ehrenstein, C. Johnson, D. Russell

In order to search for additional acetylcholinesterase (AChE) 
defects, we have isolated approximately 900 morphological and 
behavioral mutants of C.  elegans by EMS mutagenesis of strain P1000 (
ace-1 X mutant strain derived from P-D1 (unc-3 
erly called BC46.  Using an individual worm 
radiometric assay to screen these mutants for AChE activity, we have 
found one mutant, strain G-D44 (ace-2;  
missing 95%-98% of the AChE activity normally found in P1000.  This 
mutant is slightly uncoordinated, slow moving, and when tapped on the 
head with a needle, it hypercontracts and releases one or two eggs at 
a time.  A heterozygote derived by crossing G-D44 to N2 males 
segregated 1/16 UNCs (89/1191) and all of those UNCs assayed (180/180) 
were missing AChE activity.  Similarly, a heterozygote derived by 
crossing G-D44 to P1000 males segregated 1/4 UNCs (664/2910) and all 
of those UNCs assayed (105/105) were missing AChE activity.  These 
segregation results suggest that ace-1 and ace-2 are unlinked and that 
the UNC phenotype arises only when both mutations (ace-1 and ace-2) 
are homozygous in an individual.
A strain homozygous for the ace-2 mutation has been derived and 
named G202.  This strain is nearly wild type in appearance and motion 
and does not hypercontract or release eggs when tapped with a needle.  
The ace-2 (G202) mutation is on chromosome I approximately 10 map 
units from dpy-5.  We are currently constructing an ace-2; 
utant from G202 (ace-2) and P1000 (ace-1) to 
see if it has the same phenotype as G-D44.