Genome-wide characterization and transcriptional responses of Tuta absoluta glutathione S-transferases to chlorantraniliprole and spinetoram.

Tuta absoluta is a major invasive pest of Solanaceous crops, largely managed through chemical interventions. Despite its economic importance, the genomic landscape of its detoxification machinery remains poorly understood. We performed a genome-wide identification of 23 GST genes (TabsGSTs) in T. absoluta, characterized by amino acid lengths of 147-289 aa and a predominantly 1- or 5-exon genomic architecture (∼65%). The identification of four tandemly arranged gene clusters highlights potential evolutionary hotspots for insecticide resistance. Phylogenetic analysis categorized these genes into seven subfamilies, with the lineage-specific expansion of the Epsilon class indicating its key role in xenobiotic metabolism. Transcriptional profiling revealed divergent responses to insecticides: chlorantraniliprole exposure (LC50) largely failed to induce TabsGST expression, whereas spinetoram LC50 treatment triggered significant upregulation of TabsGSTe6 and TabsGSTu1. This study elucidates the molecular characteristics and expression dynamics of the GST family in T. absoluta, offering vital molecular targets for resistance monitoring and the design of targeted control measures.