Locusta migratoria Raw sequence reads. Locusta migratoria

The transition from solitary phase to gregarious phase is crucial for outbreaks of locust infestations, which threaten the agricultural and food security. Although previous studies revealed the roles of transcriptional and post-transcriptional regulations in the phase changes of locusts, the significance of translational regulation in this process is still elusive. Here, we demonstrated that several ribosomal genes displayed the strong phase-dependent expression levels and shown a molecular plasticity of ribosome profiles in gregarious and solitary locusts, respectively. Gregarious locusts exhibited significantly increased ratios of 60S/40S and polyribosomes. Moreover, ribosome profiling sequencing and mRNA-seq data showed considerably higher translational efficiency (TE) in gregarious locusts than solitary locusts. Combined with quantitative proteomics data, we observed that five genes in the most focused WGCNA and PPI cluster had consistent the change trends in protein products with TE changes. Knockdown of RP 7 in large subunit (RpL7) and RpL44 resulted in the behavior shift from gregarious towards solitary-phase-like locusts. The ribosome profiling of RpL7 RNAi locusts showed a remarkably decreased ratio of 60S/40S. Further, the RpL7 promoted loading the pale mRNA onto ribosomes leading to gregarious-like behavior of locusts. These findings have uncovered the translational regulatory mechanism of the locust phase transition, providing future pesticide targets for locust contro