| Plutella xylostella(L.)is a worldwide pest that is highly destructive and mainly harms cruciferous vegetables.The use of chemical control for a long time has resulted in extremely serious resistance to diamondback moth(DBM).Previous experimental studies found that the chlorpyrifos-resistance and-sensitive DBM to a certain degree of wing vein damage under high temperature stress.However,it is not clear whether the key genes that cause wing vein injury are related to apoptosis.In this paper,the full-length c DNAs of DBM fng and en were cloned,and their structural and evolutionary analyses were performed.The expression dynamics of fng,en and caspase-7 under heat stress were studied.RNAi of wing development-related genes fng and en was conducted by injecting ds RNA.The fng and en genes were cloned by RT-PCR and RACE technology.The full length of fng c DNA was 2094 bp.The open reading frame(ORF)of fng was1038 bp and encoded 345 amino acids.The protein molecular weight was 39.59 KDa.The en gene has a full-length c DNAof 2361 bp,contained 1152 bp of ORF,encods 383 amino acids,and a molecular weight of 42.69 KDa.Through functional domain,structural analysis and evolutionary tree analysis,the results are as follows: fng gene contains a transmembrane helix and Fringe domain structure.The en gene has a functional domain of HOX and is highly conserved.The two genes are highly conserved and are closely related to Lepidoptera insects.According to the laboratory screening of chlorpyrifos-resistant strains(Rc)and sensitive strains(Sm),Plutella xylostella,three genes of fng,en,and caspase-7 were studied with in pupae and adults of DBM in different strains under heat stress were studied using q RT-PCR technology.The results showed that the expression of fng gene in DBM pupae was most significantly down-regulated under the stress at 42 °C-8 h.Compared to normal temperature(25 °C)treatment,the expression of resistant DBM decreased by 0.88 times,and the expression of sensitive DBM decreased by 0.59 times,and the adults were most significantly down-regulated at 40 °C-16 h.The gene expression of resistant DBM was reduced by 0.66 times,and the gene expression of sensitive DBM was decreased by 0.42 times.The en gene was under the heat stress in pupae of DBM at 42 °C-8 h,the decrease was the largest.Compared to normal temperature(25 °C)treatment,the expression of resistant DBM was decreased by 0.80 times,the expression of sensitive DBM was decreased by 0.3 times,and the adults were most decreased at 42 °C-8 h,the expression of resistant DBM was reduced by0.77 times,and the expression of sensitive DBM was decreased by 0.64 times;Caspase-7 gene was most significantly up-regulated at 42 °C-4 h under heat stress of DBM.Compared to normal temperature(25 °C)treatment,the expression of resistant DBM increased by 1.51 times,and the expression of sensitive DBM increased by 1.47 times.The increase was most obvious at42 °C-4 h for adults.The expression of resistant DBM was increased by 1.75 times and that of sensitive DBM was increased by 1.55 times.The results showed that the resistance and sensitive DBM lead to wing vein damage and resistance damage is more obvious,which was previously discovered by our research group.It is may related to the expression of wing vein development genes fng and en being inhibited and significantly down-regulated and It may also be related to the apparent increase in the expression of the apoptotic gene caspase-7 and the more significant increase in the resistance of DBM.By RNA interference of diamondback moth,according to the gene expression levels in different time periods,the results showed that the expression levels of fng and en genes were significantly decreased at 4h and 8h after ds RNA injection,and the wings of most DBM were examined the veins were damaged anddisappeared,especially the Rp wing veins. |
PDF Full Text Request