Identification of Oral Secretion Proteins in Ostrinia furnacalis by Transcriptome and LC-MS/MS Analyses

Oral secretions (OS) of the Asian corn borer (Ostrinia furnacalis) play pivotal roles in its interactions with host plants. To systematically characterize the composition and potential functions of OS, 245 functionally annotated proteins from O. furnacalis reared on artificial diet were identified using an integrated approach combining transcriptomics and liquid chromatography–tandem mass spectrometry (LC-MS/MS). Bioinformatics analyses were further performed to predict 16 effector proteins. Subsequent tissue-specific expression assays were conducted to quantify the transcriptional levels of genes encoding these effector proteins in salivary glands, guts, and residual tissues. Among these genes, OfGDH2, OfPero2, OfPero3, and OfCBP were highly expressed in salivary glands, OfGDH3, OfRGD, OfEST1, OfEST2, OfMET, and Offerrin showed high expression in guts, while OfSP34 was abundantly expressed in both salivary glands and guts. This study represents the first systematic characterization of the molecular profile of O. furnacalis OS, thereby laying a solid foundation for future investigations into the molecular mechanisms underlying the host adaptation of this pest.