Worm Breeder's Gazette 14(1): 75 (October 1, 1995)

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 and nutritional regulation of glyoxylate cycle enzyme mRNA and protein expression in C. elegans

Feizhou Liu+, Jack D. Thatcher#, Henry F. Epstein#+

#Department of Neurology, and +Verna and Marrs McLean Department of Biochemistry, Baylor College of Medicine, Houston, TX 77030, USA

The expression of the C. elegans glyoxylate cycle protein (GCP) was
studied by a combination of immunofluorescence microscopy,
immunblotting, and Northern blot hybridization. The expression pattern
was found to be continued mainly in intestine and body-wall muscles in
both larvae and adults, similar to that in embryos (Liu et. al., Dev.
Biol. 167, 399-414, 1995). Immunoblotting showed that the GCP level
increased in embryogenesis, reached high level in L1 stage larvae, and
then declined to a more or less constant level during development. The
GCP mRNA expression pattern was similar to that of the protein, except
for a relatively high level in early embryos. The GCP expression was
also found to be induced by fasting in both L1 and later stages of
larvae. However, there was no significant change of the GCP levels in
the heterochronic lin-4 (lf) and lin-14 (gf) mutants compared to the N2
wild type. We conclude that the C. elegans GCP expression is
spatiotemporally regulated, and is independent of the heterochronic
lin-14 control mechanism. We propose that the increase of GCP expression
during embryogenesis, its decrease during larval development, and its
increase due to fasting in C. elegans may be related to induction by fat
catabolism and repression by carbohydrates as shown in bacterial and
fungal organisms.