C. Buesa et al., BLATTELLA-GERMANICA HAS 2 HMG-COA SYNTHASE GENES - BOTH ARE REGULATEDIN THE OVARY DURING THE GONADOTROPIC CYCLE, The Journal of biological chemistry, 269(16), 1994, pp. 11707-11713
The isoprenoid pathway leads to various essential non-sterol products
in insects. These end products have a crucial role in growth, differen
tiation, sexual maturation, and reproduction. 3-Hydroxy-3-methylglutar
yl coenzyme A (HMG-CoA) synthase (EC 4.1.3.5.) has generally been cons
idered one of the committed steps of the pathway. We had previously re
ported the cloning of a cytosolic HMG-CoA synthase cDNA in Blattella g
ermanica; we have now isolated and characterized a new cDNA clone for
HMG-CoA synthase in this insect. Analysis of this 1716 base pair cDNA
reveals a deduced protein of 455 residues with a molecular mass of 51,
424 Da. The two HMG-CoA synthases have 69% identical amino acid residu
es, and both lack an N-terminal leader peptide to target the protein i
nto mitochondria. This HMG-CoA synthase cDNA can revert the Chinese ha
mster ovary-K1-derived cell line, Mev-1, which is a defective mutant f
or HMG-CoA synthase. Both HMG-CoA synthase genes are expressed differe
ntly throughout development. Analysis of adult tissues shows higher ex
pression in ovary and fat body. The expression of HMG-CoA synthase (EC
4.1.3.5.) and reductase (EC 1.1.1.34) genes during the gonadotrophic
cycle in B. germanica shows that the three genes of the isoprenoid pat
hway are developmentally regulated in the ovary.