diapause hormone
7.When the silkworms incubated under lower temperature and all-day dark conditions were injected with a synthesized diapause hormone on the third day after pupation, 70% of them were induced to lay diapause eggs, in which the activities of carbohydrate metabolism-related enzymes, Gpase, PFK, FBP and NAD-SDH, in the diapause period were different from those of the non-diapause eggs and were similar to those of the natural diapause eggs.
9.With diapause pupae of oriental tobacco budworm ?(Helicoverpa assulta? Guenée), a double?strand cDNA fragment of DH (diapause hormone) gene was obtained from RT?PCR amplification. The fragment was linked with pET?30a(+) plasmid and then the recombinant plasmid was transformed into Escherichia coli BL21. Sequence analysis showed that the insertion fragment of recombinant plasmid was complete and the reading frame was correct.
10.By using pEGM-3Z as vectors,the reporter plasmids were constructed with a luciferase gene under the control of trehalase gene promoters from Bombyx mori and Bombyx mandarina respectively for transient expression in insect cell lines. Meanwhile,the regulatory effect of diapause hormone(DH) on the transcriptional activity of trehalase gene promoter was studied.
