Juvenile hormone bisepoxide biosynthesis in vitro by the ring gland of Drosophila melanogaster: a putative juvenile hormone in the higher Diptera.

Abstract

The in vitro production of juvenile hormone (JH) was investigated by using isolated ring glands from third instar Drosophila melanogaster. A JH-like molecule is secreted that comigrates with a synthetic sample of methyl 6,7;10,11-bisepoxy-3,7,11-trimethyl-(2E)-dodecenoate (JHB3) during TLC, liquid chromatography, and GC analysis. Purified product from farnesoic acid-stimulated ring glands was analyzed by electron impact GC/MS and gave a mass spectrum identical to synthetic JHB3. Additional structure confirmation was obtained following conversion of product from unstimulated biosynthesis to a derivative that comigrated on liquid chromatography with the derivative prepared from synthetic JHB3. Physiological studies revealed that JHB3 is produced solely by the corpus allatum portion of the ring gland in vitro. Isolated ring glands from other cyclorrhaphous dipteran larvae also produce JHB3 almost exclusively in vitro. Corpora allata from mosquito larvae, however, produce only JH III, indicating that JHB3 production may be restricted to the higher Diptera. Topically applied synthetic JHB3 caused developmental responses in newly formed D. melanogaster white puparia similar to those obtained with JH III. The data suggest that JHB3 is a fly juvenile hormone.

Characterization of Drosophila melanogaster cytochrome P450 genes

“…No clear orthologue to Cyp15a1 is identifiable in D. melanogaster (28). However, unlike in D. punctata, JH III bisepoxide (JHB 3 ) is thought to be the major JH produced in D. melanogaster (70). JHB 3 is synthesized by an alternate pathway possibly involving 2 epoxidation reactions catalyzed by a P450, converting farnesoic acid to JHB 3 (71).…”

Juvenile Hormone Biosynthesis in Diapause and Nondiapause Females of the Adult Blow Fly Protophormia terraenovae

“…In addition to JHB 3 , JH III and MF are also found as products in the CA in Phormia regina (Yin et al, 1995) and Neobellieria bullata (Bylemans et al, 1998). But in Lucilia cuprina (Lefevere et al, 1993), Drosophila melanogaster (Richard et al, 1989) and Calliphora vomitoria (Cusson et al, 1991) the production of JH III or MF is negligible. This is also true in P. terraenovae.…”

“…A combination of the radiochemical assay and various chromatographic analyses, such as TLC, high performance liquid chromatography and gas chromatography-mass spectrometry has demonstrated that the CA and ring glands in cyclorrhaphous flies predominantly biosynthesize JHB 3 (Yin, 1994). JHB 3 has been identified first in Drosophila melanogaster (Richard et al, 1989) and later in other cyclorrhaphous species (Yin and Stoffolano, 1997). In addition to JHB 3 , JH III and MF are also found as products in the CA in Phormia regina (Yin et al, 1995) and Neobellieria bullata (Bylemans et al, 1998).…”

Molecular Evolution of Juvenile Hormone Signaling

“…JH 0, I, II, and III have all been isolated from lepidopteran insects, whereas JH III, the presumed evolutionary precursor to the higher homologs, is found in all insects. JH bisepoxide (JHB3) has been identified as a product of the corpus allatum (CA) in higher Diptera including Drosophila melanogaster and Sarcophaga bullata (Richard et al, 1989;Bylemans et al, 1998). Nearly identical in structure to JH III, JHB3 is distinguished by an additional epoxide group spanning C6-C7.…”