Journal of invertebrate pathology最新文献

{"title":"A honey bee-associated virus remains infectious and quantifiable in postmortem hosts","authors":"Alexandria N. Payne ,&nbsp;Vincent Prayugo ,&nbsp;Adam G. Dolezal","doi":"10.1016/j.jip.2024.108258","DOIUrl":"10.1016/j.jip.2024.108258","url":null,"abstract":"<div><div>Corpse-mediated pathogen transmission is a viable route through which naïve hosts can become infected, but its likelihood for honey bee-associated viruses is largely unknown. While these viruses can be easily detected in deceased bees, it remains unclear if they stay infectious within postmortem hosts or if enough viral RNA degradation—and subsequently virus inactivation—occurs post-host death to render these viruses inviable. This knowledge gap has important implications for how researchers perform honey bee virus studies and for our general understanding of honey bee virus transmission. To better understand the resiliency of honey bee-associated viruses within deceased hosts, we first tested the hypothesis that postmortem specimens, stored in colony-normal temperature and humidity conditions, can be reliably used to quantify virus abundance. To determine this, we experimentally-infected adult honey bees with Israeli acute paralysis virus (IAPV) and then measured the virus levels of individuals sampled live or at different postmortem time points (4, 12, 24, and 48 hours post-death) using RT-qPCR and a standard curve absolute quantification method. We found no significant differences based on when bees were sampled, indicating that postmortem honey bees are statistically comparable to using live-sampled bees and can be reliably used to quantify absolute IAPV abundance. We then performed a follow-up experiment that determined whether or not the IAPV detected in postmortem bees remained infectious over time. We found that IAPV extracted from postmortem bees remained highly infectious for at least 48 hours post-death, indicating that any viral RNA degradation that may have occurred during the postmortem interval did not adversely affect IAPV’s overall infectivity. The results from this study suggest that IAPV is more resilient to degradation than previously assumed, support the use of postmortem bees for downstream IAPV analyses, and indicate that postmortem hosts can act as sources of IAPV infection for susceptible individuals.</div></div>","PeriodicalId":16296,"journal":{"name":"Journal of invertebrate pathology","volume":"209 ","pages":"Article 108258"},"PeriodicalIF":3.6,"publicationDate":"2024-12-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142818344","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A mycoviral infection drives virulence and ecological fitness of the entomopathogenic fungus Beauveria bassiana","authors":"F. Rueda-Maíllo ,&nbsp;I. Garrido-Jurado ,&nbsp;I. Kotta-Loizou ,&nbsp;E. Quesada-Moraga","doi":"10.1016/j.jip.2024.108251","DOIUrl":"10.1016/j.jip.2024.108251","url":null,"abstract":"<div><div>Entomopathogenic ascomycetes are important natural regulators of insect pest populations and an increasingly adopted microbial control option. Fungal virulence in entomopathogenic ascomycetes can be modified by mycoviruses, viruses that infect fungi, whereas the possible role of these viruses on the physical and biochemical properties of the virus-containing fungal strains and on their ecological fitness has remained largely unexplored. Here, utilizing a <em>Beauveria bassiana</em> strain naturally infected with two mycoviruses, Beauveria bassiana partitivirus 2 (BbPV-2) and Beauveria bassiana polymycovirus 1 (BbPmV-1), we found that the mycovirus-containing strain is hypervirulent towards the experimental insect <em>Galleria mellonella</em> and shows major physical and biochemical changes in spore size, isoelectric point, and Pr1 activity, but even more impactful, the mycoviral infection confers a significant environmental- abiotic and biotic stress tolerance to the fungus. Hence, mycovirus infection expanded the temperature range for fungal growth and germination, and improved tolerance to osmotic stress, water stress, and UV-B radiation. Similarly, the antagonistic activity of the mycovirus-containing strain against <em>Trichoderma harzianum</em> was increased as compared to the mycovirus-free one. Taken together, these data suggest for the first time a mycovirus related adaptation of key traits indicators of environmental competence of a beneficial fungus, rendering these mycoviruses as potent tools for entomopathogenic fungal strain selection and development as mycoinsecticides.</div></div>","PeriodicalId":16296,"journal":{"name":"Journal of invertebrate pathology","volume":"209 ","pages":"Article 108251"},"PeriodicalIF":3.6,"publicationDate":"2024-12-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142791702","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Pristionchus – Beetle associations: Towards a new natural history","authors":"Ralf J. Sommer","doi":"10.1016/j.jip.2024.108243","DOIUrl":"10.1016/j.jip.2024.108243","url":null,"abstract":"<div><div>The free-living nematode <em>Pristionchus pacificus</em> has been established as a model system in integrative evolutionary biology by combining laboratory studies with field work and evolutionary biology. Multiple genetic, molecular and experimental tools and a collection of more than 2,500 <em>P. pacificus</em> strains and more than 50 <em>Pristionchus</em> species, which are available as living cultures or frozen stock collections, support research on various life history traits. Species of <em>Pristionchus</em> exhibit a number of complex traits unknown from <em>Caenorhabditis elegans</em> and most other free-living nematodes. First, <em>P. pacificus</em> can form two alternative mouth forms, an example of developmental plasticity that is increasingly studied to investigate the role of plasticity as a facilitator of evolutionary novelty. More than a decade of work has identified associated genetic and epigenetic mechanisms and revealed the evolutionary and ecological significance of feeding structure plasticity. Second, one of the two mouth morphs results in predatory behavior against other nematodes and is currently used to investigate the neurobiology of predation. Third, potential predation results in the risk of cannibalism among conspecifics. Strikingly, <em>Pristionchus</em> nematodes have developed a self-recognition system that allows the distinction of self (kin) and non-self. Given all these organismal features, this nematode has recently been considered a key example for research towards a new natural history (<span><span>West-Eberhard, 2024</span></span>). Here, I summarize recent work on <em>Pristionchus</em> with a focus on a ‘new natural history’. In addition, I review some recent studies that indicate an interaction of <em>Pristionchus</em> with EPNs that was suggested based on various surveys in different ecological habitats.</div></div>","PeriodicalId":16296,"journal":{"name":"Journal of invertebrate pathology","volume":"209 ","pages":"Article 108243"},"PeriodicalIF":3.6,"publicationDate":"2024-12-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142791758","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Ultrastructural changes in epithelial cells on different stages of sinantropic muscoid dipterans fed with spores of Brevibacillus laterosporus","authors":"Lorrane de Andrade Pereira ,&nbsp;Sandra Maria de Oliveira Souza ,&nbsp;Margareth Maria de Carvalho Queiroz ,&nbsp;Rafael Meyer Mariante ,&nbsp;Viviane Zahner","doi":"10.1016/j.jip.2024.108238","DOIUrl":"10.1016/j.jip.2024.108238","url":null,"abstract":"<div><div><em>Brevibacillus laterosporus</em> is a sporulating bacteria, with typical canoe-shaped parasporal bodies attached to the spores. It has shown great biotechnological potential, including its broad pathogenic spectrum against different orders of insects and other invertebrates with medical-veterinary-sanitary importance. The high degree of synanthropy of muscoid dipterans and the damage they cause being a source of myiasis and carriers of pathogens encourage research into their population control. The objective of the study was to evaluate the histopathological effects caused by <em>B. laterosporus</em> NRS 590 on larvae and adults of <em>M. domestica</em> and <em>C. megacephala</em>. The flies were collected in garbage dumpsters, identified and the respective colonies were adapted to laboratory conditions (air-conditioned chamber with regulated humidity and temperature). Different concentrations of bacterial spore suspensions were offered to neo larvae and adults. Larvae and adults were dissected and intestinal epithelial cells of the flies, in temporal kinetics, were demonstrated using transmission electron microscopy (TEM) techniques. Irregular microvilli were observed in the intestines of both adult and larvae tested after 6 h of treatment. At 12 h and 24 h, intense cellular disorganization was observed and at 24 h and 48 h there was discontinuity of microvilli, cell extrusion and nuclear damage in some cells, as well. Spores of <em>B. laterosporus</em> NRS590 produce histopathological effects on both larvae and adults of synanthropic flies, being an alternative active principle in eco-friendly insecticides.</div></div>","PeriodicalId":16296,"journal":{"name":"Journal of invertebrate pathology","volume":"209 ","pages":"Article 108238"},"PeriodicalIF":3.6,"publicationDate":"2024-12-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142791774","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Distinct biological control agents differentially modulate the immune system of the sugarcane borer larvae (Diatraea saccharalis)","authors":"Manoely Abreu Reis ,&nbsp;Felipe Marinho Coutinho de Souza ,&nbsp;Ianne Caroline da Silva Nobre ,&nbsp;Fátima Maryelen Gomes de Fraga Dias ,&nbsp;Maria Fátima Grossi-de-Sá ,&nbsp;José Dijair Antonino","doi":"10.1016/j.jip.2024.108241","DOIUrl":"10.1016/j.jip.2024.108241","url":null,"abstract":"<div><div>The humoral response plays a crucial role in insect defense against parasites and pathogens, typically producing antimicrobial peptides through the Toll, IMD, and Jak-STAT signaling pathways, as well as melanization via phenoloxidases. However, many studies use nonpathogenic or opportunistic organisms and often infect insects in nonnatural ways, such as piercing or injecting the pathogen into the hemocoel. The objective of this study was to examine the modulation of the main humoral pathway genes involved in the interaction between the nonmodel organism <em>Diatraea saccharalis</em> (the sugarcane borer) and different biological control agents. We identified and evaluated the expression of <em>DsDorsal</em> (Toll pathway), <em>DsRelish</em> (IMD pathway), <em>DsSTAT</em> (JAK/STAT pathway), <em>DsPPO1</em>, and <em>DsPPO2</em> (PO pathway) in larvae and pupae of <em>D. saccharalis</em> exposed or not to different biological control agents. The biocontrol agents used were: (i) the bacterium <em>Bacillus thuringiensis</em> var. <em>aizawai</em> GC-91, which is pathogenic to <em>D. saccharalis</em>; (ii) the fungus <em>Metarhizium anisopliae</em> ESALQE9 strain, which is employed to control the froghoppers of the genus <em>Mahanarva</em> in sugarcane fields, though it exhibits low virulence to <em>D. saccharalis</em>; and (iii) the generalist parasitoid <em>Tetrastichus howardi</em>. Our results demonstrate that <em>B. thuringiensis</em> at LC₃₀ induced the expression of <em>DsRelish</em> at 24 h and <em>DsSTAT</em> at 48 h after treatment initiation. In contrast, treatment with the <em>M. anisopliae</em> ESALQE9 strain reduced the levels of <em>DsDorsal</em> and <em>DsSTAT</em> 24 h post-infection compared to the control group. In larvae, <em>DsDorsal</em>, <em>DsSTAT</em>, <em>DsPPO1</em>, and <em>DsPPO2</em> were induced in response to <em>T. howardi</em>, whereas no induction was observed in pupae. Notably, no immune-related genes were modulated during the pupae-parasitoid interaction. Additionally, we provide an explanation for why <em>T. howardi</em> shows superior parasitism success in <em>D. saccharalis</em> pupae compared with larvae. The data presented here introduce novel perspectives for enhancing pest management through the utilization of biocontrol agents.</div></div>","PeriodicalId":16296,"journal":{"name":"Journal of invertebrate pathology","volume":"209 ","pages":"Article 108241"},"PeriodicalIF":3.6,"publicationDate":"2024-12-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142791788","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Sequence independent immune effects of white spot syndrome virus (WSSV) dsRNA complexed with phytoglycogen nanoparticles in freshwater crayfish","authors":"Kayla A. Samms ,&nbsp;Emma C. Monod ,&nbsp;Aizah Ijaz ,&nbsp;Sarah Au ,&nbsp;Kristof Jenik ,&nbsp;Tania Rodríguez-Ramos ,&nbsp;Brian Dixon ,&nbsp;Stephanie J. DeWitte-Orr","doi":"10.1016/j.jip.2024.108239","DOIUrl":"10.1016/j.jip.2024.108239","url":null,"abstract":"<div><div>White spot syndrome virus (WSSV), a double stranded (ds)DNA virus, is a pathogen that causes massive mortalities in crustaceans worldwide. The present study focuses on using dsRNA to induce sequence-independent immune responses to control virus replication. DsRNA is a well characterized innate immune stimulant in vertebrates and effectively induces an antiviral state. In crustaceans, it has been shown that dsRNA containing WSSV sequences (WSSV-dsRNA) can trigger an immune response independent of RNA interference (RNAi) to mitigate disease. We hypothesized that the potency and efficacy of dsRNA-induced immunity would be enhanced using a biodegradable, cationic phytoglycogen nanoparticle, Nanodendrix (nanoparticle; NP), to deliver the dsRNA. Two <em>in vivo</em> studies were conducted to test the efficacy of long dsRNA as an innate immune stimulant with or without the NP in crayfish. Long dsRNA, 360–500 bp in length, was synthesized based on two WSSV sequences, viral particle 28 (VP28) and viral particle 19 (VP19) respectively. Crayfish were injected in the ventral sinus with WSSV-dsRNA (VP28 or VP19 sequence) either in complex with the NP or alone. High molecular weight (HMW) poly inosinic: polycytidylic acid (poly IC), a synthetic viral dsRNA mimic, was used as a positive control. In the negative control groups, crayfish were injected with either phosphate buffered saline or NP alone. These studies found WSSV-dsRNA could enhance hemocyte numbers, nitric oxide levels and phenoloxidase activity. This enhancement was more effective than when using HMW poly IC. Finally, the nanoparticle did not increase dsRNA’s immune activation capability, but it did reduce dsRNA’s toxicity. Further studies may help determine the efficacy of these treatments as immune stimulants for preventing pathogenic outbreaks in the invertebrate aquaculture industry.</div></div>","PeriodicalId":16296,"journal":{"name":"Journal of invertebrate pathology","volume":"209 ","pages":"Article 108239"},"PeriodicalIF":3.6,"publicationDate":"2024-12-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142785947","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Host-specific patterns of virulence and gene expression profiles of the broad-host-range entomopathogenic fungus Metarhizium anisopliae","authors":"Natasha Sant Anna Iwanicki ,&nbsp;Isabella Alice Gotti ,&nbsp;Italo Delalibera Jr. ,&nbsp;Henrik H. De Fine Licht","doi":"10.1016/j.jip.2024.108242","DOIUrl":"10.1016/j.jip.2024.108242","url":null,"abstract":"<div><div>Generalist pathogens with a broad host range encounter many different host environments. Such generalist pathogens are often highly versatile and adjust their expressed phenotype to the host being infected. Species in the fungal genus <em>Metarhizium</em> (Hypocreales: Clavicipitaceae) occupy various ecological niches, including plant rhizosphere symbionts, soil saprophytes, and insect pathogens with applications in biological control of pests. The species <em>M. anisopliae</em> is highly diverse combining the capability of association with plant roots and infection of a broad range of arachnid and insect hosts, from agricultural pests to vectors of human disease. It is among the most studied and applied biological control agents worldwide. Here, we investigate the phenotypic plasticity and differential gene expression of <em>M. anisopliae</em> blastospores during infection of different insect hosts. First, the virulence of <em>M. anisopliae</em> blastospores was evaluated against <em>Tenebrio molitor</em> (Coleoptera: Tenebrionidae)<em>, Spodoptera frugiperda</em> (Lepidoptera: Noctuidae), <em>Gryllus assimilis</em> (Orthoptera: Gryllidae), and <em>Apis mellifera</em> (Hymenoptera: Apidae)<em>.</em> Second, the percentage of appressorium formation on the membranous wings of the four hosts was determined, and third, the fungal transcriptome profile during penetration on the hosts was analyzed. Our findings reveal that <em>M. anisopliae</em> blastospores exhibit high virulence against <em>Tenebrio molitor</em>, with significantly higher appressorium formation on beetle wings compared to the other three tested insects. We also document distinct gene expression patterns in <em>M. anisopliae</em> blastospores during insect infection of <em>T. molitor, S. frugiperda,</em> and <em>A. mellifera</em>, with notable variations observed in <em>G. assimilis</em>. These differences are associated with the expression of enzymes involved in the degradation of specific compounds present in each insect wing, as well as hydrophobins, destruxins, and specialized metabolites related to virulence. The study emphasizes the differences in fungal gene expression during infection of the four insect orders and highlights the virulence-related genes specific to each infective process.</div></div>","PeriodicalId":16296,"journal":{"name":"Journal of invertebrate pathology","volume":"209 ","pages":"Article 108242"},"PeriodicalIF":3.6,"publicationDate":"2024-12-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142780358","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Phagostimulant MTSG supplementation benefits growth-promoting and defensive effects of Rhodobacter azotoformans on Chinese mitten crab Eriocheir sinensis","authors":"Xurui Zheng ,&nbsp;Li He ,&nbsp;Lefu Wen ,&nbsp;La Xu ,&nbsp;Youhong Wang ,&nbsp;Haipeng Cao ,&nbsp;Chunlei Gai ,&nbsp;Jian An","doi":"10.1016/j.jip.2024.108240","DOIUrl":"10.1016/j.jip.2024.108240","url":null,"abstract":"<div><div>The use of phagostimulant and <em>Rhodobacter</em> has been well proposed in Chinese mitten crab <em>Eriocheir sinensis</em> culture. Yet the influence of phagostimulant supplementation on the growth-promoting and defensive effects of <em>Rhodobacter</em> on Chinese mitten crabs is still unknown. In this study, a 40-day feeding trial was carried out to examine the contribution of dietary phagostimulant MTSG to the effects of <em>R. azotoformans</em> on the growth performance, immunity, antioxidant capability, intestinal flora diversity, and resistance of <em>E. sinensis</em> to bacterial challenge. The results revealed higher weight gain, specific growth rate, as well as serum and hepatopancreatic acid phosphatase, alkaline phosphatase, superoxide dismutase, and catalase activities in the 3.0 to 9.0 g/kg diet MTSG + <em>R. azotoformans</em>-fed crabs than <em>R. azotoformans</em>-fed crabs, indicating that the supplementation of MTSG at 3.0 to 9.0 g/kg diet could improve the effect of <em>R. azotoformans</em> on growth performance, immunity and antioxidant capability of Chinese mitten crabs. Furthermore, the supplementation of MTSG at 3.0 to 9.0 g/kg diet could strengthen the effect of <em>R. azotoformans</em> on intestinal flora diversity of Chinese mitten crabs, and enhance the effect of <em>R. azotoformans</em> on the disease resistance against <em>S. putrefaciens</em> infection. To the best of our knowledge, this is the first study to reveal the contribution of a phagostimulant (MTSG) to the growth-promoting and defensive effects of <em>R. azotoformans</em> on Chinese mitten crabs.</div></div>","PeriodicalId":16296,"journal":{"name":"Journal of invertebrate pathology","volume":"208 ","pages":"Article 108240"},"PeriodicalIF":3.6,"publicationDate":"2024-11-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142747887","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Bombyx mori PAT4 gene inhibits BmNPV infection and replication through autophagy","authors":"Kaifang Jia ,&nbsp;Jinyang Wang ,&nbsp;Dan Jiang ,&nbsp;Xiangrui Ding ,&nbsp;Qiaoling Zhao ,&nbsp;Dongxu Shen ,&nbsp;Zhiyong Qiu ,&nbsp;Xuelian Zhang ,&nbsp;Cheng Lu ,&nbsp;Heying Qian ,&nbsp;Dingguo Xia","doi":"10.1016/j.jip.2024.108235","DOIUrl":"10.1016/j.jip.2024.108235","url":null,"abstract":"<div><div>Proton-assisted amino acid transporter 4 (PAT4) is a member of the solute carrier (SLC) 36 family, which mediates the transmembrane transport of amino acids and their derivatives. However, the function of <em>PAT4</em> in <em>Bombyx mori</em> is not clear. In this study, <em>BmPAT4</em> was cloned and identified using PCR technology. Its open reading frame (ORF) includes 1,395 bp, encoding 464 amino acid (Aa). Moreover, the sequence of BmPAT4 has the highest similarity with wild <em>Bombyx.mandarina</em>, <em>Spodoptera frugiperda</em> and <em>Spodoptera litura</em>, and it has ten transmembrane domains. BmPAT4 was localized in the cell membrane and expressed in all tissues of the silkworm. After <em>Bombyx mori</em> nuclear polyhedrosis virus (BmNPV) infection, the expression of <em>BmPAT4</em> in midgut, hemolymph and fat body was significantly up-regulated. In addition, overexpression of <em>BmPAT4</em> in BmN cells could significantly inhibit the proliferation of BmNPV, and the expression of several genes in autophagy pathway decreased significantly. On the contrary, down-regulation of <em>BmPAT4</em> expression by RNA interference can promote BmNPV replication and proliferation, and the expression of key genes in autophagy pathway is significantly increased. This is the first time to report that <em>BmPAT4</em> has an antiviral effect in silkworm. Moreover, the silkworm activates <em>BmTORC1</em> via <em>BmPAT4</em>, which inhibits autophagy in silkworm cells, resulting in a lack of energy and raw materials for BmNPV infection and replication in cells.</div></div>","PeriodicalId":16296,"journal":{"name":"Journal of invertebrate pathology","volume":"208 ","pages":"Article 108235"},"PeriodicalIF":3.6,"publicationDate":"2024-11-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142695318","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Inheritance of Cry2Ab2 resistance in two Helicoverpa zea (Lepidoptera: Noctuidae) populations resistant to single- and dual-Bacillus thuringiensis proteins","authors":"Fangneng Huang ,&nbsp;Wenbo Yu ,&nbsp;Graham P. Head ,&nbsp;Ying Niu ,&nbsp;Caroline Sakuno ,&nbsp;Shucong Lin ,&nbsp;Tiago Silva ,&nbsp;Bhavana Patla","doi":"10.1016/j.jip.2024.108237","DOIUrl":"10.1016/j.jip.2024.108237","url":null,"abstract":"<div><div>Cry2Ab2 is a <em>Bacillus thuringiensis</em> (Bt) protein that has been pyramided with Cry1A.105 in transgenic maize and Cry1Ac in cotton to control some major lepidopteran pests including the corn earworm/bollworm, <em>Helicoverpa zea</em> (Boddie). However, the widespread occurrence of resistance of this pest to the pyramided Cry1A/Cry2A crops in the southern region of the United State has become a threat to the sustainability of the technology. In this study, multiple genetic crosses and backcrosses were developed to characterize the inheritance of Cry2Ab2 resistance in two <em>H. zea</em> populations resistant to the single protein, Cry2Ab2 (RR_2Ab) and the dual proteins in Bt maize, Cry1A.105/Cry2Ab2 (RR_VT2P). Diet-overlay bioassays with F1 hybrids from reciprocal crosses between a susceptible and the resistant populations showed that the Cry2Ab2 resistance in both RR_2Ab and RR_VT2P was inherited autosomally and non-recessively. Segregation tests in F2 and backcrossed generations indicated that the resistance was likely controlled by more than one locus. The effective dominance levels of the resistance estimated at each of three discriminating concentrations were similar between RR_2Ab and RR_VT2P, ranging from incompletely dominant to incompletely recessive. The similar inheritance observed in RR_2Ab and RR_VT2P suggests that the Cry2Ab2 resistance is independent from the Cry1A.105 resistance. The non-recessive inheritance of the resistance could be an important factor causing the widespread resistance of this insect to the Cry1A/Cry2A crops in the southern region. Implications of the observed inheritance properties in Bt crop resistance management are discussed.</div></div>","PeriodicalId":16296,"journal":{"name":"Journal of invertebrate pathology","volume":"208 ","pages":"Article 108237"},"PeriodicalIF":3.6,"publicationDate":"2024-11-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142667916","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"生物学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}