Costruzione di linee transgeniche di Bombyx mori caratterizzate da dsRNA interference costitutiva del gene orologio period

Bombyx mori transgenic lines for the induction of constitutive dsRNA interference of the clock gene period. The circadian clock of insects consists of interlocking transcriptional feedback loops which are positively and negatively regulated by the complex interaction of a number of "clock" genes and their protein products. One of these genes, period (per), plays a central role in the core of the circadian oscillator of the dipteran Drosophila melanogaster. Mutations in this gene lead to alterations in circadian rhythmicity and developmental timing. In order to establish whether similar effects can also be observed in other insects, we employed a construct suitable for the embryonic transformation of the lepidopteran Bombyx mori. This construct was engineered to allow specific ds RNA interference-induced post-transcriptional gene silencing of the Bombyx per gene. A preliminary molecular characterization of the resulting transformants shows that several independent transgenic lines harboring variable numbers of transgenes were obtained.