Insights into chlorantraniliprole resistance of Chilo suppressalis: Expression profiles of ATP-binding cassette transporter genes in strains ranging from low- to high-level resistance

Abstract

• 34 of 47 ABC genes were differentially expressed in three chlorantraniliprole resistant strains. • CsABCA1 , -D2 , and -H2 were up-regulated in all resistant strains. • CsABCF1 , -G11 , and -G12 were down-regulated in the highest resistant strain (resistance ratio = 249.6) • The expression trend for ABC genes fit a descending curve from low- to high-level resistance. The ATP-binding cassette (ABC) proteins are involved in trans-cellular transport of substances at inverse concentrations. After ABC genes were discovered to be involved in multidrug resistance in humans, increased attention was paid to the role of insect ABC genes in pesticide resistance. Chilo suppressalis , the most important Lepidopteran pest in rice production, has developed resistance to the insecticide chlorantraniliprole. However, few of the ABC genes that contribute to chlorantraniliprole resistance have been studied . Here, 47 genes encoding ABC transporters were identified, including five CsABCA , seven CsABCB , ten CsABCC , two CsABCD , one CsABCE , three CsABCF , 15 CsABCG, and four CsABCH genes. The expression profiles of these transporter genes were determined in three chlorantraniliprole-resistant strains: R1, R2, and HR, with a resistance ratio of 38.8, 110.4, and 249.6, respectively. CsABCA1 , -D2, and -H2 were up-regulated in all resistant strains, and the trend in the transcript levels of all 47 CsABC genes fitted a descending curve from R1 to HR. Unexpectedly, CsABCF1 , -G11 and -G12 were significantly down-regulated in HR. These results provide new insights into the roles of ABC transporters in chlorantraniliprole resistance in C. suppressalis .