Worm Breeder's Gazette 5(2): 33

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.

DNA and Nuclear Terminal Phenotypes of the Embryonic Lethals of C. elegans

R. Hecht, S. Fairlie, J. Schratweiser, J. Oro, D. Schomer, A. Bartel, E. Hungerford

Figure 1

We have now completed the DNA terminal phenotypes for the B set of 
embryonic lethals of C.  elegans.  Flow cytometry was used to measure 
the total DNA content of 18 embryonic lethals maintained at 
restrictive temperature (25 C) for 20 hours.  The enclosed Table 
provides these DNA terminal phenotypes as well as three (63'0', 44T, 
11Y) from our Houston set of conditional embryonic lethals.  The 
number of independent separate determinations is shown in parenthesis 
and the total number of embryos analyzed per sample ranged from 3,000 
to 270,000 (the average is about 20K to 100K).  Cell stages (or 
nuclear DNA equivalents) that contain more than 8% of the total number 
of embryos are blocked out in this Table.
The above DNA terminal phenotypes are now being complemented by the 
direct embryonic squash technique.  The results that we have obtained 
are: (1) the average DNA content observed by flow cytometry is 
reflected by a similar average number of nuclei for several mutants; (
2) several embryonic lethals give rise to abnormally enlarged (
polyploid) nuclei, and (3) several mutants demonstrate that cleavage 
is independent of nuclear division.  They exhibit blastomeres that do 
not contain nuclei.
[See Figure 1]