Molecular cloning, characterization, and expression profiling analysis of Cry toxin receptor genes from sugarcane shoot borer Chilo infuscatellus (Snellen)

Abstract

The sugarcane shoot borer Chilo infuscatellus (Snellen) is known for causing severe damage to sugarcane yield in China. Methods have been developed to control this pest, including Cry toxin pesticide and transgenic Bt plants. In order to investigate the molecular mechanism of the Cry toxin binding process and provide a basis for understanding the insect's resistance mechanism, we used a high throughput sequencing platform to perform a de novo transcriptome assembly across different larval developmental stages and analyzed Cry toxin receptors based on our assembled transcripts. We cloned twelve Cry toxin receptor genes including 1 cadherin (Cad), 7 aminopeptidase-Ns (APNs), 3 alkaline phosphatases (ALPs), and 1 ATP-binding cassette transporter subfamily C2 (ABCC2), and three of them with full length. The sublethal dosage of Cry1Ac toxin was applied to sugarcane shoot borer and identified some Cry toxin receptor genes that were significantly induced after 48 h of exposure. Furthermore, quantitative RT-PCR was conducted to detect the expression profiles of these genes. Our transcriptome sequence data provided a valuable molecular resource for further study and the identified Cry toxin receptor data gave insights for improved research into the mechanism of Bt resistance.

Keywords: Chilo infuscatellus; Cry toxin receptor; Expression profile; Sublethal dosage.