Worm Breeder's Gazette 7(2): 29b

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.

Developmental Regulation of Two Glyceraldehyde-3-Phosphate Dehydrogenases in C. elegans

P.O. Yarbrough, R.M. Hecht

We are studying the developmental regulation of two isoenzymes of 
glyceraldehyde-3-phosphate dehydrogenase (G3PDH) in the small nematode,
Caenorhabditis ned by starch gel 
electrophoresis, the embryonic specific isoenzyme, G3PDH-1, disappears 
during post-embryonic development.  In contrast, the faster migrating 
isoenzyme, G3PDH-2, increases its activity during post-embryogenesis.  
In order to elucidate the molecular mechanism(s) underlying the 
temporal and/or spatial differential expression of G3PDH-1 and G3PDH-2 
we have optimized the following G3PDH purification scheme.  Both 
enzymes were purified to near homogeneity by ammonium sulfate 
fractionation, gel filtration and NAD-agarose affinity chromatography. 
Complete homogeneity as well as the separation of both isoenzymes was 
achieved by preparative 'chromatofocusing.'  Both isoenzymes exhibited 
identical native and subunit molecular weights of 131,000 and 38,500, 
respectively.
We believe that these two isoenzymes are encoded by separate genes 
because opposite mobilities were observed for these two isoenzymes in 
the related nematode, Caenorhabditis briggsae.  To confirm this 
hypothesis, partial peptide analysis of each purified isoenzyme in 
Caenorhabditis conducted.