Preliminary Study On The Relationship Between Gene Ran And Deltamethrin Resistance

DM (Deltamethrin), a synthetic dibromo-pyrethroid insecticide, is well known to possess high activity against a broad spectrum of insects, to lack persistence in the environment and to have low acute toxicity in mammals. Despite the significant role of synthetic pyrethroid insecticides in insect control programs, the emergence of a large number of insects' resistant to insecticide has become a major obstacle for insect control. Resistance mechanism involves a large number of genes. Therefore, discovering and exploring resistance-associated genes is critical.Our previous studies suggested that the fusion gene UBL40 is a DM resistance-associated gene. In another study, we found nuclear protein L40 to be the functionally important gene in the resistance to DM. We postulate that a nuclear protein may play an important role in DM stess reaction. To further explore the relationship between nuclear genes and DM stess reaction,2-DE and MALDI-TOF-TOF analyses were used. The results revealed that the expression of the nuclear gene Ran was significantly improved after treatment with DM. This implies that Ran may be a member of DM stress inducible gene family that inhibits apoptosis.The GTP-binding nuclear protein Ran has mostly been reported to be an essential player in nuclear transport, chromosome alignment, microtubule dynamics, centrosome duplication, kinetochore attachment of microtubules, nuclear-envelope dynamics and phagocytosis. However, until now, there has been no report showing the involvement of Ran in insecticide resistance. In this paper, two-dimensional electrophoresis analysis showed that the expression level of Ran in Kc cells in response to deltamethrin (DM) was higher than that in the control group. In addition, quantitative analysis using RT-PCR (real-time PCR) revealed that the expression of Ran was obviously upregulated at various concentrations of DM. Western blot analysis showed that Ran was up-regulated 2.27-fold over the control at 48 h. Because we still could not pinpoint whether Ran was actually involved in DM stress reaction, to further verify the role of Ran in stress reaction, RNA interference and cell transfection were utilized. Overexpression of Ran in cells conferred a degree of protection against DM after 72 h. Furthermore, interference with Ran significantly increased the susceptibility to DM. All of the above findings strongly imply that Ran may participate in the development of stress reaction to DM. Therefore, investigating the possible role of Ran in DM detoxification will broaden our limited knowledge regarding DM stress inducible genes.