Worm Breeder's Gazette 5(2): 42a

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.

Title unknown.

Authors unknown.

In the wild-type Caenorhabditis ei of the 
hypodermal syncytium assume an ordered and predictable spatial pattern 
as new nuclei are added during development (Sulston and Horvitz, Dev.  
Biol., 56 110 (1977)).  These nuclei are displaced by animal 
contortions but return to equilibrium positions when the distorting 
force is removed.  In the recessive mutant e1753 (LG I), the syncytial 
nuclei are not permanently anchored and move along the syncytium 
freely.  Defective nuclear attachment is apparent in several other 
cell types with geometries favorable for observing nuclear 
displacement.  It is possible that all cell types in the animal are 
affected.
The mutant animals are fertile (50-130 progeny) and coordinated.  
They are slightly small, pale, and short-lived.  (This may account for 
their reduced brood size.) The active movements of the male and female 
pronuclei following fertilization and the cell lineages appear normal.
In addition to nuclear positioning, mitochondrial positioning is 
disturbed in this mutant.  Normally, the shape and precise spatial 
distribution of mitochondria varies with the metabolic state of the 
worm.  However, in e1753, the mitochondria of the lateral hypodermis 
are easily seen to move freely.  The mitochondria of living worms can 
be seen by staining in 10  g/ml rhodamine 6G in M9 buffer for 30 
minutes (Johnson et al., PNAS 77 990 (February 1980)).  The stained 
worms are placed on an NGM plate with a bacterial lawn and transferred 
to a microscope slide with a 5% agar pad for immediate viewing by 
epifluorescence.  The worms will remain stained for several hours on 
the bacterial lawn.
This mutation, e1753, may disrupt cytoskeletal elements responsible 
for the positioning of mitochondria and interphase nuclei.