Studies On Cytochrome P450s Expression Differences Under Gossypol Induction In Aphis Gossypii Glover

In this study, an important pest of cotton aphid (Aphis gossypii Glover,Homoptera: Aphididae) was chosen as the research object. Several methods ofgossypol inducing cotton aphid were screened in order to investigate the geneexpression differences induced by gossypol. The differently expressed genes undergossypol induction were analyzed through gene expression profiling and quantitativereal time PCR combinded with bioinformatics analysis.After the comparision between several methods of gossypol inducing, dippingmethod and spraying method were chosen to calculate gossypol treatment group andblank control group of cotton aphids.Gene expression profiles of cotton apid were achieved by gene expressionprofiles sequencing. Through bioinformatics analysis,36differentially expressedgenes were confirmed. The majority of these genes are related with aminoacid, organic acid, carboxylic acid transportation and transmembrane transportationfunctions. The other important differentially expressed genes encode cytochromeb-c1complex subunit, cuticular protein precursor and e3ubiquitin ligase. Cytochromeb-c1complex play an important role in the process of oxidative phosphorylation. Thedifferent expression of cuticular protein precursor means lower cuticularpenetration rate. Insects can detoxificate more gossypol by delaying the arrival timeof gossypol to target sites. E3ubiquitin ligase expression level changes may regulatethe expression of P450genes in cotton aphid, and it confirmed that the in-vivometabolism of gossypol might be associated with some P450enzymes. Thenphylogenetic tree of cotton aphid P450genes was constructed to estimate theirphylogenetic according to the gene expression profiles library. Then anotherphylogenetic tree of cotton aphid Cnc-C gene and other Cnc genes from NCBI wasconstructed. Further, an expression vector of Cnc-C gene was constructed to analysisits function of regulating P450genes expression.By quantitative real-time PCR, several P450genes expression differences onmRNA level under varieties of gossypol concentration and treating time were analized.In400ppm and600ppm concentration of gossypol treatment, significant up-regulated expression was found in most of these genes. Only a few genes were unsignificantlychanged or down-regulated. More than half of the genes expression level increasedwith the increase of gossypol concentration and treatment time. Under the sameconcentration treatment, the expression of several genes increased with time increase,and the expression of remaining genes reach the maximum in a shorter time and keepconstant or even decline. It’s notable that several genes expression level changed morethan1000times, such as CYP315A1、CYP6A14etc.Above all, this study provides an important theoretical basis for the molecularmechanism of Aphis gossypii induced by gossypol and an experimental basis forrevealing the adaptability of cottom aphids under exogenous toxic substances. Thiswas important to the effective control of cotton aphid.