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N6‐methyladenosine (m6A) plays a key role in many biological processes. However, the function and evolutionary relationship of m6A‐related genes in insects remain largely unknown. Here we analysed the phylogeny of m6A‐related genes among 207 insect species and found that m6A‐related genes are evolutionarily conserved in insects. Subcellular localization experiments of m6A‐related proteins in BmN cells confirmed that BmYTHDF3 was localized in the cytoplasm, BmMETTL3, BmMETTL14, and BmYTHDC were localized in the nucleus, and FL2D was localized to both the nucleus and cytoplasm. We examined the expression patterns of m6A‐related genes during the embryonic development of Bombyx mori. To elucidate the function of BmMETTL3 during the embryonic stage, RNA sequencing was performed to measure changes in gene expression in silkworm eggs after BmMETTL3 knockdown, as well as in BmN cells overexpressing BmMETTL3. The global transcriptional pattern showed that knockdown of BmMETTL3 affected multiple cellular processes, including oxidoreductase activity, transcription regulator activity, and the cation binding. In addition, transcriptomic data revealed that many observed DEGs were associated with fundamental metabolic processes, including carbon metabolism, purine metabolism, amino acid biosynthesis, and the citrate cycle. Interestingly, we found that knockdown of BmMETTL3 significantly affected Wnt and Toll/Imd pathways in embryos. Taken together, these results suggest that BmMETTL3 plays an essential role in the embryonic development of B. mori, and deepen our understanding of the function of m6A‐related genes in insects. [ABSTRACT FROM AUTHOR]

Lipocalins exhibit functional diversity, including roles in retinol transport, invertebrate cryptic coloration, and stress response. However, genome‐wide identification and characterization of lipocalin in the insect lineage have not been thoroughly explored. Here, we found that a lineage‐specific expansion of the lipocalin genes in Lepidoptera occurred in large part due to tandem duplication events and several lipocalin genes involving insect coloration were expanded more via tandem duplication in butterflies. A comparative analysis of conserved motifs showed both conservation and divergence of lepidopteran lipocalin family protein structures during evolution. We observe dynamic changes in tissue expression preference of paralogs in Bombyx mori, suggesting differential contribution of paralogs to specific organ functions during evolution. Subcellular localization experiments revealed that lipocalins localize to the cytoplasm, nuclear membrane, or nucleus in BmN cells. Moreover, several lipocalin genes exhibited divergent responses to abiotic and biotic stresses, and 1 lipocalin gene was upregulated by 300 fold in B. mori. These results suggest that lipocalins act as signaling components in defense responses by mediating crosstalk between abiotic and biotic stress responses. This study deepens our understanding of the comprehensive characteristics of lipocalins in insects. [ABSTRACT FROM AUTHOR]

A three-dimensional (3D) image reconstruction method for the spinning target based on the radar network is proposed in this letter and the design concept is sourced from the similarity of the two-dimensional (2D) imaging result with the target’s mapping on the imaging plane. The proposed method has the capacity to generate 3D image of the spinning target by reconstructing the scattering distribution in 3D Cartesian space. Firstly, the inverse Radon transform is applied to obtain the imaging result of the spinning target and the mapping formulas for mapping the air points onto the 2D image plane are derived. In addition, the radar network 3D image reconstruction model for the spinning target is constructed and the corresponding algorithm for solving the reconstruction model is proposed. Finally, some experiment results are given to verify the effectiveness of the proposed method. [ABSTRACT FROM AUTHOR]