Insect Molecular Biology最新文献

{"title":"An association between Dnmt1 and Wnt in the production of oocytes in the whitefly Bemisia tabaci","authors":"Christopher B. Cunningham,&nbsp;Emily A. Shelby,&nbsp;Elizabeth C. McKinney,&nbsp;Alvin M. Simmons,&nbsp;Allen J. Moore,&nbsp;Patricia J. Moore","doi":"10.1111/imb.12893","DOIUrl":"10.1111/imb.12893","url":null,"abstract":"<p>The function of DNA methylation in insects and the DNA methyltransferase (<i>Dnmt</i>) genes that influence methylation remains uncertain. We used RNA interference to reduce the gene expression of <i>Dnmt1</i> within the whitefly <i>Bemisia tabaci (Hemiptera:Aleyrodidae; Gennadius)</i>, a hemipteran species that relies on <i>Dnmt1</i> for proper gametogenesis. We then used RNA-seq to test an <i>a priori</i> hypothesis that meiosis-related genetic pathways would be perturbed. We generally did not find an overall effect on meiosis-related pathways. However, we found that genes in the <i>Wnt</i> pathway, genes associated with the entry into meiosis in vertebrates, were differentially expressed. Our results are consistent with <i>Dnmt1</i> knockdown influencing specific pathways and not causing general transcriptional response. This is a finding that is also seen with other insect species. We also characterised the methylome of <i>B. tabaci</i> and assessed the influence of <i>Dnmt1</i> knockdown on cytosine methylation. This species has methylome characteristics comparable to other hemipterans regarding overall level, enrichment within gene bodies, and a bimodal distribution of methylated/non-methylated genes. Very little differential methylation was observed, and difference in methylation were not associated with differences in gene expression. The effect on <i>Wnt</i> presents an interesting new candidate pathway for future studies.</p>","PeriodicalId":13526,"journal":{"name":"Insect Molecular Biology","volume":"33 5","pages":"467-480"},"PeriodicalIF":2.3,"publicationDate":"2024-02-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1111/imb.12893","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139712018","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Pleiotropic immunoregulation by growth-blocking peptide in Ostrinia furnacalis","authors":"Dongchun Hu,&nbsp;Fuqiang Xu,&nbsp;Zupeng Gao,&nbsp;Kangkang Chen,&nbsp;Wenlong Guo,&nbsp;Zitian Wang,&nbsp;Shuzhong Li,&nbsp;Congjing Feng","doi":"10.1111/imb.12898","DOIUrl":"10.1111/imb.12898","url":null,"abstract":"<p>Insects rely on their innate immune system to eliminate pathogenic microbes. As a system component, cytokines transmit intercellular signals to control immune responses. Growth-blocking peptide (GBP) is a member of the stress-responsive peptide family of cytokines found in several orders of insects, including <i>Drosophila</i>. However, the physiological role of GBP in defence against pathogens is not thoroughly understood. In this study, we explored the functions of GBP in a lepidopteran pest, <i>Ostrinia furnacalis</i>. Injection of recombinant <i>O. furnacalis</i> GBP (<i>Of</i>GBP) precursor (proGBP) and chemically synthesised GBP significantly induced the transcription of antimicrobial peptides (AMPs) and other immunity-related genes including immune deficiency (<i>IMD</i>) and <i>Dorsal</i>. The level of <i>Of</i>GBP mRNA was upregulated after bacterial infection. Knockdown of <i>Of</i>GBP expression led to a decrease in <i>IMD</i>, <i>Relish</i>, <i>MyD88</i> and <i>Dorsal</i> mRNA levels. <i>Of</i>GBP induced phenoloxidase activity and affected hemocyte behaviours in <i>O. furnacalis</i> larvae. In summary, GBP is a potent cytokine, effectively regulating AMP synthesis, melanization response and cellular immunity to eliminate invading pathogens.</p>","PeriodicalId":13526,"journal":{"name":"Insect Molecular Biology","volume":"33 3","pages":"270-282"},"PeriodicalIF":2.6,"publicationDate":"2024-02-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139702408","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Studying the role of Bombyx mori molybdenum cofactor sulfurase in Bombyx mori nucleopolyhedrovirus infection","authors":"Jun-li Lv,&nbsp;Wen-qing Lai,&nbsp;Yu-quan Gong,&nbsp;Kai-yi Zheng,&nbsp;Xiao-ying Zhang,&nbsp;Xue-yang Wang,&nbsp;Li-shang Dai,&nbsp;Mu-wang Li","doi":"10.1111/imb.12895","DOIUrl":"10.1111/imb.12895","url":null,"abstract":"<p>Molybdenum cofactor sulfurase (MoCoS) is a key gene involved in the uric acid metabolic pathway that activates xanthine dehydrogenase to synthesise uric acid. Uric acid is harmful to mammals but plays crucial roles in insects, one of which is the immune responses. However, the function of <i>Bombyx mori MoCoS</i> in response to BmNPV remains unclear. In this study, <i>BmMoCoS</i> was found to be relatively highly expressed in embryonic development, gonads and the Malpighian tubules. In addition, the expression levels of <i>BmMoCoS</i> were significantly upregulated in three silkworm strains with different levels of resistance after virus infection, suggesting a close link between them. Furthermore, RNAi and overexpression studies showed that <i>BmMoCoS</i> was involved in resistance to BmNPV infection, and its antivirus effects were found to be related to the regulation of uric acid metabolism, which was uncovered by inosine- and febuxostat-coupled RNAi and overexpression. Finally, the BmMoCoS-mediated uric acid pathway was preliminarily confirmed to be a potential target to protect silkworms from BmNPV infection. Overall, this study provides new evidence for elucidating the molecular mechanism of silkworms in response to BmNPV infection and new strategies for the prevention of viral infections in sericulture.</p>","PeriodicalId":13526,"journal":{"name":"Insect Molecular Biology","volume":"33 3","pages":"246-258"},"PeriodicalIF":2.6,"publicationDate":"2024-02-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139697307","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Suppressing the expression of glutathione S-transferase gene GSTd10 increases the sensitivity of Zeugodacus cucurbitae against β-cypermethrin","authors":"Xiao-Di Zhai,&nbsp;Shi-Heng Wang,&nbsp;Meng Ma,&nbsp;Deng Pan,&nbsp;Jin-Jun Wang,&nbsp;Dong Wei","doi":"10.1111/imb.12892","DOIUrl":"10.1111/imb.12892","url":null,"abstract":"<p><i>Zeugodacus cucurbitae</i> Coquillett (Diptera: Tephritidae) is an agriculturally and economically important pest worldwide that has developed resistance to <i>β</i>-cypermethrin. Glutathione <i>S</i>-transferases (GSTs) have been reported to be involved in the detoxification of insecticides in insects. We have found that both <i>ZcGSTd6</i> and <i>ZcGSTd10</i> were up-regulated by <i>β</i>-cypermethrin induction in our previous study, so we aimed to explore their potential relationship with <i>β</i>-cypermethrin tolerance in this study. The heterologous expression of ZcGSTd6 and ZcGSTd10 in <i>Escherichia coli</i> showed significantly high activities against 1-chloro-2,4-dinitrobenzene (CDNB). The kinetic parameters of ZcGSTd6 and ZcGSTd10 were determined by Lineweaver–Burk. The <i>V</i>_max and <i>K</i>_m of ZcGSTd6 were 0.50 μmol/min·mg and 0.3 mM, respectively. The <i>V</i>_max and <i>K</i>_m of ZcGSTd10 were 1.82 μmol/min·mg and 0.53 mM. The 3D modelling and molecular docking results revealed that <i>β</i>-cypermethrin exhibited a stronger bounding to the active site SER-9 of ZcGSTd10. The sensitivity to <i>β</i>-cypermethrin was significantly increased by 18.73% and 27.21%, respectively, after the knockdown of <i>ZcGSTd6</i> and <i>ZcGSTd10</i> by using RNA interference. In addition, the inhibition of CDNB at 50% (IC₅₀) and the inhibition constants (<i>Ki</i>) of <i>β</i>-cypermethrin against ZcGSTd10 were determined as 0.41 and 0.33 mM, respectively. The <i>Ki</i> and IC₅₀ of <i>β</i>-cypermethrin against ZcSGTd6 were not analysed. These results suggested that <i>ZcGSTd10</i> could be an essential regulator involved in the tolerance of <i>Z. cucurbitae</i> to <i>β</i>-cypermethrin.</p>","PeriodicalId":13526,"journal":{"name":"Insect Molecular Biology","volume":"33 3","pages":"218-227"},"PeriodicalIF":2.6,"publicationDate":"2024-02-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139691752","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The hAT family hopper transposon exists as highly similar yet discontinuous elements in the Bactrocera tephritid fly genus","authors":"Alfred M. Handler,&nbsp;Richard B. Furlong","doi":"10.1111/imb.12891","DOIUrl":"10.1111/imb.12891","url":null,"abstract":"<p>The <i>hAT</i> family transposable element, <i>hopper</i>, was originally discovered as a defective 3120-bp full-length element in a wild-type strain of the oriental fruit fly, <i>Bactrocera dorsalis</i> (Hendel) (Diptera: Tephritidae), and subsequently a functional 3131-bp element, <i>hopper</i>^Bdwe, was isolated from a <i>white eye</i> mutant strain. The latter study showed that closely related elements exist in melonfly, <i>Zeugodacus cucurbitae</i> (Coquillett) (Diptera: Tephritidae), a closely related subgenus, suggesting that <i>hopper</i> could have a widespread presence in the <i>Bactrocera</i> genus. To further understand the distribution of <i>hopper</i> within and beyond the <i>B. dorsalis</i> species complex, primer pairs from <i>hopper</i>^Bdwe and its adjacent genomic insertion site were used to survey the presence and relatedness of <i>hopper</i> in five species within the complex and four species beyond the complex. Based on sequence identity of a 1.94 kb internal nucleotide sequence, the closest relationships were with mutated elements from <i>B. dorsalis</i> s.s. and species synonymized with <i>B. dorsalis</i> including <i>B. papayae</i>, <i>B. philippinensis</i> and <i>B. invadens</i>, ranging in identity between 88.4% and 99.5%. Notably, <i>Bactrocera carambolae</i> (Drew &amp; Hancock) (Diptera: Tephritidae), which is most closely related to <i>B. dorsalis</i> beyond the synonymized species, shared <i>hopper</i> identities of 97.3%–99.5%. Beyond the <i>B. dorsalis</i> complex, <i>Z. cucurbitae,</i> <i>Bactrocera tryoni</i> (Froggatt) (Diptera: Tephritidae) and <i>Bactrocera zonata</i> (Saunders) (Diptera: Tephritidae) shared identities of 83.1%–97.1%, while <i>hopper</i> was absent from the <i>Bactrocera oleae</i> (Gmelin) (Diptera: Tephritidae) strain tested. While the functional autonomous <i>hopper</i>^Bdwe element was not detected in these species, another closely related <i>hopper</i> element isolated from a <i>B. dorsalis</i> genetic sexing strain has an uninterrupted transposase open reading frame. The discontinuous presence of <i>hopper</i> in the <i>Bactrocera</i> genus has implications for its use for genomic manipulation and understanding the phylogenetic relationship of these species.</p>","PeriodicalId":13526,"journal":{"name":"Insect Molecular Biology","volume":"33 3","pages":"185-194"},"PeriodicalIF":2.6,"publicationDate":"2024-01-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139512394","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Identification and function of the Pax gene Bmgsb in the silk gland of Bombyx mori","authors":"Hongguo Yang,&nbsp;Yongping Xu,&nbsp;Yutong Yuan,&nbsp;Xuebing Liu,&nbsp;Jikailang Zhang,&nbsp;Jiaojiao Li,&nbsp;Ran Zhang,&nbsp;Jun Cao,&nbsp;Tingcai Cheng,&nbsp;Chun Liu","doi":"10.1111/imb.12886","DOIUrl":"10.1111/imb.12886","url":null,"abstract":"<p>Paired box (<i>Pax</i>) genes are highly conserved throughout evolution, and the Pax protein is an important transcription factor of embryonic development. The <i>Pax</i> gene <i>Bmgsb</i> is expressed in the silk glands of silkworm, but its biological functions remain unclear. This study aimed to investigate the expression pattern of <i>Bmgsb</i> in the silk gland and explore its functions using RNA interference (RNAi). Here, we identified eight <i>Pax</i> genes in <i>Bombyx mori</i>. Phylogenetic analysis showed that the <i>B. mori Pax</i> genes were highly homologous to the <i>Pax</i> genes in other insects and highly evolutionarily conserved. The tissue expression profile showed that <i>Bmgsb</i> was expressed in the anterior silk gland and anterior part of the middle silk gland (AMSG). RNAi of <i>Bmgsb</i> resulted in defective development of the AMSG, and the larvae were mostly unable to cocoon in the wandering stage. RNA-seq analysis showed that the fibroin genes <i>fib-l</i>, <i>fib-h</i> and <i>p25</i>, cellular heat shock response-related genes and phenol oxidase genes were considerably upregulated upon <i>Bmgsb</i> knockdown. Furthermore, quantitative reverse transcription-PCR results showed that the fibroin genes and ubiquitin proteolytic enzyme-related genes were significantly upregulated in the AMSG after <i>Bmgsb</i> knockdown. This study provides a foundation for future research on the biological functions of <i>B. mori Pax</i> genes. In addition, it demonstrates the important roles of <i>Bmgsb</i> in the transcriptional regulation of fibroin genes and silk gland development.</p>","PeriodicalId":13526,"journal":{"name":"Insect Molecular Biology","volume":"33 3","pages":"173-184"},"PeriodicalIF":2.6,"publicationDate":"2024-01-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139491201","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Reminiscences on the honeybee genome project and the rise of epigenetic concepts in insect science","authors":"Ryszard Maleszka","doi":"10.1111/imb.12888","DOIUrl":"10.1111/imb.12888","url":null,"abstract":"<p>The sequencing of the honeybee genome in 2006 was an important technological and logistic achievement experience. But what benefits have flown from the honeybee genome project? What does the annotated genomic assembly mean for the study of behavioural complexity and organismal function in honeybees? Here, I discuss several lines of research that have arisen from this project and highlight the rapidly expanding studies on insect epigenomics, emergent properties of royal jelly, the mechanism of nutritional control of development and the contribution of epigenomic regulation to the evolution of sociality. I also argue that the term ‘insect epigenetics’ needs to be carefully redefined to reflect the diversity of epigenomic toolkits in insects and the impact of lineage-specific innovations on organismal outcomes. The honeybee genome project helped pioneer advances in social insect molecular biology, and fuelled breakthrough research into the role of flexible epigenomic control systems in linking genotype to phenotype.</p>","PeriodicalId":13526,"journal":{"name":"Insect Molecular Biology","volume":"33 5","pages":"444-456"},"PeriodicalIF":2.3,"publicationDate":"2024-01-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1111/imb.12888","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139402644","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Constitutively expressed small heat shock protein LsHsp21.5 not only enhances heat tolerance but also helps to maintain reproduction in female Laodelphax striatellus","authors":"Xue Xia,&nbsp;Feng Zhu,&nbsp;Hongtao Niu,&nbsp;Lei Pan,&nbsp;Zhouting Zheng,&nbsp;Lingyun Pan,&nbsp;Ary A. Hoffmann,&nbsp;Jichao Fang,&nbsp;Lihua Wang","doi":"10.1111/imb.12889","DOIUrl":"10.1111/imb.12889","url":null,"abstract":"<p>Coping with stressful conditions and maintaining reproduction are two key biological processes that affect insect population dynamics. Small heat shock proteins (sHSPs) are involved in the stress response and the development of insects. The <i>sHsp</i> gene <i>Laodelphax striatellus</i> (Hemiptera: Delphacidae) <i>sHsp 21.5</i> (<i>LsHsp21.5</i>) showed constitutive, stage- and organ-specific expression in <i>L. striatellus</i>, a pest that damages cultivated rice in east Asia. The expression of <i>LsHsp21.5</i> was highest in the ovary, with 43.60, 12.99 and 1.45 time higher expression here than in the head, gut and female fat bodies, respectively. The expression of this gene was weakly affected by heat or cold shock. The gene provided in vitro protection against heat damage to malate dehydrogenase and in vivo protection against heat stress in <i>Escherichia coli</i> (Enterobacteriales: Enterobacteriaceae) BL21(DE3) and <i>L. striatellus</i>. Moreover, <i>L. striatellus</i> reproduction decreased by 1.85 times when the expression of <i>LsHsp21.5</i> was inhibited by RNA interference. The expression of some genes related to reproduction, such as the homologous gene of chorion protein, also declined. These results suggest that <i>LsHsp21.5</i> expression not only protects other proteins against stress but also helps maintain the stable expression of some reproduction-related genes under non-stressful conditions, with impacts on <i>L. striatellus</i> fecundity.</p>","PeriodicalId":13526,"journal":{"name":"Insect Molecular Biology","volume":"33 3","pages":"195-205"},"PeriodicalIF":2.6,"publicationDate":"2024-01-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139110860","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A parasitoid regulates 20E synthesis and antibacterial activity of the host for development by inducing host nitric oxide production","authors":"Minli Dai,&nbsp;Zhe Jiang,&nbsp;Fanchi Li,&nbsp;Jing Wei,&nbsp;Bing Li","doi":"10.1111/imb.12890","DOIUrl":"10.1111/imb.12890","url":null,"abstract":"<p>Parasitoids are important components of the natural enemy guild in the biological control of insect pests. They depend on host resources to complete the development of a specific stage or whole life cycle and thus have evolved towards optimal host exploitation strategies. In the present study, we report a specific survival strategy of a fly parasitoid <i>Exorista sorbillans</i> (Diptera: Tachinidae), which is a potential biological control agent for agricultural pests and a pest in sericulture. We found that the expression levels of nitric oxide synthase (NOS) and nitric oxide (NO) production in host <i>Bombyx mori</i> (Lepidoptera: Bombycidae) were increased after <i>E</i>. <i>sorbillans</i> infection. Reducing NOS expression and NO production with an NOS inhibitor (NG-nitro-L-arginine methyl ester hydrochloride) in infected <i>B</i>. <i>mori</i> significantly impeded the growth of <i>E</i>. <i>sorbillans</i> larvae. Moreover, the biosynthesis of 20-hydroxyecdysone (20E) in infected hosts was elevated with increasing NO production, and inhibiting NOS expression lowered 20E biosynthesis. More importantly, induced NO synthesis was required to eliminate intracellular bacterial pathogens that presumably competed for shared host resources. Inhibiting NOS expression down-regulated the transcription of antimicrobial peptide genes and increased the number of bacteria in parasitized hosts. Collectively, this study revealed a new perspective on the role of NO in host–parasitoid interactions and a novel mechanism for parasitoid regulation of host physiology to support its development.</p>","PeriodicalId":13526,"journal":{"name":"Insect Molecular Biology","volume":"33 3","pages":"206-217"},"PeriodicalIF":2.6,"publicationDate":"2024-01-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139097773","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Function analysis and characterisation of a novel chitinase, MdCht9, in Musca domestica","authors":"Wen-Jing Zhao,&nbsp;Yan Li,&nbsp;Zhen-Long Jiao,&nbsp;Pei-Pei Su,&nbsp;Long-Bing Yang,&nbsp;Chao-Qin Sun,&nbsp;Jiang-Fan Xiu,&nbsp;Xiao-Li Shang,&nbsp;Guo Guo","doi":"10.1111/imb.12887","DOIUrl":"10.1111/imb.12887","url":null,"abstract":"<p>Insect chitinases have been proposed as potential targets for pest control. In this work, a novel group IV chitinase gene, <i>MdCht9</i>, from <i>Musca domestica</i> was found to have multiple functions in the physiological activity, including chitin regulation, development and antifungal immunity. The <i>MdCht9</i> gene was cloned and sequenced, its phylogeny was analysed and its expression was determined in normal and 20E treated larvae. Subsequently, RNA interference (RNAi)-mediated <i>MdCht9</i> knockdown was performed, followed by biochemical assays, morphological observations and transcriptome analysis. Finally, the recombinant protein <i>MdCht9</i> (rMdCht9) was purified and tested for anti-microbial activity and enzyme characteristics. The results showed that <i>MdCht9</i> consists of three domains, highly expressed in a larval salivary gland. RNAi silencing of <i>MdCht9</i> resulted in significant down-regulation of chitin content and expression of 15 chitin-binding protein (CBP) genes, implying a new insight that <i>MdCht9</i> might regulate chitin content by influencing the expression of CBPs. In addition, more than half of the lethality and partial wing deformity appeared due to the <i>dsMdCht9</i> treatment. In addition, the rMdCht9 exhibited anti-microbial activity towards <i>Candida albicans</i> (fungus) but not towards <i>Escherichia coli</i> (G−) or <i>Staphylococcus aureus</i> (G+). Our work expands on previous studies of chitinase while providing a potential target for pest management.</p>","PeriodicalId":13526,"journal":{"name":"Insect Molecular Biology","volume":"33 2","pages":"157-172"},"PeriodicalIF":2.6,"publicationDate":"2023-12-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139061985","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}