Cloning and response to gravity of the silkworm dynein light chain 8 gene

To study the changes of the silkworm dynein light chain 8 (DlcS) gene expression pattern in different gravitational environments. The open reading frame sequence of Dlc8 gene was amplified and analyzed. The distribution of Dlc8 gene was investigated in embryo, head, silk gland, midgut, cuticle, blood, fat, tuba malpighii of silkworm respectively. The effects of simulated gravitational environments (0 g , 1 g, 2 g) produced by large gradient high magnetic field (LGHMF) on expression of the silkworm Dlc8 gene were tested by RT-PCR and real time RT-PCR in BmN cells. Expression of the silkworm Dlc8 gene in simulated weightless environment was tested by real time RT-PCR in inverse period and in total embryo period of silkworm. The Dlc8 gene with 270 bp coding 323 aa was successfully amplified. The homology rates of amino acid sequences of Dlc8 gene between silkworm and A rabidopsis·thaliana, Drosophίla melanogaster, Caenorhabdìtts elegans, Xenopus tropicalis, Mus musculus, Homo sapiens were 67%, 96%, 91%, 95%, 92%, 92%, respectively. Signal peptide analysis showed that Dlc8 was not a secretion protein. There was not glycosyl-phosphatidyl inositol anchor site in Dlc8 amino acid sequence. Molecular mass and isoelectric point of Dlc8 were 10.34 ku and 6.81, respectively. Dlc8 gene is conservative in embryo, head, silk gland, midgut, cuticle, blood, fat, tuba malpighii of silkworm. Dlc 8 gene is more sensitive to gravity than magnetic field in BmN cells. There are different responses to gravity on Dlc8 gene expression in different period of silkworm embryo. There was no significant change of Dlc8 gene expression between simulated weightless and control groups. The results showed that Dlc8 gene could be the molecular target to study gravity bioeffect. This research may contribute to reveal the mechanism of gravity bioeffect of the silkworm Dlc8 gene.