Entomological Science (2000) 3, 9-18

Yiping Zheng, Hajime Sugie and Sumio Tojo (2000)
Juvenile hormone titre and hormonal regulation of storage protein synthesis in the common cutworm, Spodoptera litura
Entomological Science 3 (1), 9-18
Abstract: SIM-GC-Mass analysis demonstrated only the presence of JH II in the haemolymph of Spodoptera litura reared in crowded conditions. JH II level decreased dramatically near final larval ecdysis and was undetectable one day after the ecdysis. Northern blot analysis of the fat body total RNA revealed that the transcription of genes encoding the two basic and methionine-rich storage proteins, SL-1 and SL-2, started 24 hr after the ecdysis, nearly at the time of their first appearance in the haemolymph. The synthesis was suppressed by the injection of JH analogue, methoprene to the newly ecdysed larvae. Methoprene injection 24 hr after ecdysis had no affect. The latter treatment shortened the instar duration without uptake of three storage proteins from the haemolymph by the fat body and induced supernumerary ecdysis to seventh instar. These results suggest that the synthesis of SL-1 and SL-2 are suppressed by JH II at the pre-transcription level, and that the disappearance of JH II triggers the transcription of their genes whereby the transcription becomes refractory to JH thereafter. Methoprene treatment had no effect on the other storage protein, SL-3 (arylphorine).
(The abstract is excluded from the Creative Commons licence and has been copied with permission by the publisher.)
Database assignments for author(s): Sumio Tojo

Research topic(s) for pests/diseases/weeds:
general biology - morphology - evolution

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Pest and/or beneficial records:

Beneficial	Pest/Disease/Weed	Crop/Product	Country	Quarant.
	Spodoptera litura		Japan