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The development of insect appendages requires the expression of multiple genes in a strict spatial and temporal order. The odd‐skipped family genes are vital transcriptional factors involved in embryonic development. The development and morphogenesis of the insect wing requires multiple transcription factors to regulate the expression of wing patterning genes at the transcriptional level. However, the function of odd‐related genes in insect wing morphogenesis and development during postembryonic stages is unclear. We focused on the roles of the sister of odd and bowl (sob) gene, a member of odd‐skipped family genes, during the wing morphopoiesis in Bombyx mori using the clustered regularly interspaced palindromic repeats (CRISPR)/CRISPR‐associated protein 9 system and in Tribolium castaneum by RNA interference. The results showed that the wings were significantly smaller and degenerated, and wing veins were indistinct in the sob gene loss‐of‐function group in both B. mori and T. castaneum. Quantitative real‐time polymerase chain reaction revealed that the Tcsob gene regulated the expression of wing development genes, such as the cht 7 and the vg gene. The findings suggest the importance of sob gene in insect wing morphology formation during postembryonic stages. [ABSTRACT FROM AUTHOR]

Pheromone‐binding proteins (PBPs) are thought to bind and transport sex pheromones onto the olfactory receptors on the dendrite membrane of olfactory neurons, and thus play a vital role in sex pheromone perception. However, the function of PBPs has rarely been demonstrated in vivo. In this study, two PBPs (PBP1 and PBP3) of Chilo suppressalis, one of the most notorious pyralid pests, were in vivo functionally characterized using insects with the PBP gene knocked out by the CRISPR/Cas9 system. First, through direct injection of PBP‐single guide RNA (sgRNA)/Cas9 messenger RNA into newly laid eggs, a high rate of target‐gene editing (checked with polled eggs) was induced at 24 h after injection, 21.3% for PBP1‐sgRNA injected eggs and 19.5% for PBP3‐sgRNA injected eggs. Second, by an in‐crossing strategy, insects with mutant PBP1 or PBP3 (both with a premature stop codon) were screened, and homozygous mutants were obtained in the G3 generation. Third, the mutant insects were measured for electroantennogram (EAG) response to female sex pheromones. As a result, both PBP mutant males displayed significant reduction in EAG response, and this reduction in PBP1 mutants was higher than that in PBP3 mutants, indicating a more important role of PBP1. Finally, the relative importance of two PBPs and the possible off target effect induced by sgRNA‐injection are discussed. Taken together, our study provides a deeper insight into the function of and interaction between different PBP genes in sex pheromone perception of C. suppressalis, as well as a valuable reference in methodology for gene functional study in other genes and other moth species. [ABSTRACT FROM AUTHOR]