Low-density lipoprotein receptor-related protein 2(LRP2)is required for lipid export in the midgut of the migratory locust,Locusta migratoria

Low-density lipoprotein receptor-related protein 2(LRP2)is a multifunctional endocytic receptor expressed in epithelial cells.In mammals,it acts as an endocytic receptor that mediates the cellular uptake of cholesterol-containing apolipoproteins to maintain lipid homeostasis.However,little is known about the role of LRP2 in lipid homeostasis in insects.In the present study,we investigated the function of LRP2 in the migratory locust Locusta migratoria(LmLRP2).The mRNA of LmLRP2 is widely distributed in various tissues,including integument,wing pads,foregut,midgut,hindgut,Malpighian tubules and fat body,and the amounts of LmLRP2 transcripts decreased gradually in the early stages and then increased in the late stages before ecdysis during the nymphal developmental stage.Fluorescence immunohistochemistry revealed that the LmLRP2 protein is mainly located in cellular membranes of the midgut and hindgut.Using RNAi to silence LmLRP2 caused molting defects in nymphs(more than 60%),and the neutral lipid was found to accumulate in the midgut and surface of the integument,but not in the fat body,of dsLmLRP2-treated nymphs.The results of a lipidomics analysis showed that the main components of lipids(diglyceride and triglyceride)were significantly increased in the midgut,but decreased in the fat body and hemolymph.Furthermore,the content of total triglyceride was significantly increased in the midgut,but markedly decreased in the fat body and hemolymph in dsLmLRP2-injected nymphs.Our results indicate that LmLRP2 is located in the cellular membranes of midgut cells,and is required for lipid export from the midgut to the hemolymphand fat body in locusts.

Azole selenourea disrupted the midgut and caused malformed development of Plutella xylostella

Chemical insecticides targeting the digestive system of diamondback moth(DBM),Plutella xylostella,have not been developed.The discovery of an insecticide with novel mode of action is a challenge for the control of DBM.In this study,a class of selenium-and difluoromethyl-modified azoles(fluoroazole selenoureas,FASU)were designed and synthesized for the control of DBM.Of these azoles,compound B4 showed the highest insecticidal activity against DBM.The LC50of third-and second-instar larvae reached 32.3 and 4.6μg mL^(–1),respectively.The midgut tissue of larvae was severely disrupted,and the larval intestinal tissue was dotted with unique red spots after treatment with compound B4.Compound B4 led to disintegration of the peritrophic matrix,swelling of the midgut epithelium,fracture of the microvilli,and extensive leakage of cellular debris in the midgut lumen.Surviving larvae grew very slowly,and the larval duration was significantly prolonged after exposure to compound B4 at sublethal doses(LC10,LC25and LC50).Furthermore,the pupation rate,emergence rate and pupae weight were significantly decreased.Compound B4 also induced abnormal pupae,causing adults to be trapped in the cocoon or failure to fly due to twisted wings.These results demonstrated that FASU could reduce the population of DBM in sublethal doses.FASU is the first synthetic insecticidal lead compound that has been shown to disrupt the midgut tissue of the larvae of DBM,and its mode of action totally differs from that of commercial chemical insecticides.

家蚕蛹变态期的中肠发育变化观察及细胞凋亡与自噬相关基因的表达检测

为探究家蚕中肠在蛹变态过程中的形态发育变化,于家蚕5龄幼虫期、蛹期及蛾期以24h为间隔,对其中肠进行解剖观察,结果显示:家蚕5龄幼虫的中肠为长圆筒形,在食桑期呈绿色、膨大的管状,进入熟蚕期停止食桑后,中肠开始变黄、缩短;在熟蚕营茧化蛹的过程中,中肠持续缩短、变小,并随着发育时期的延长,最终呈椭圆形颗粒状,表面颜色由浅黄色变为棕黄色。进一步观察家蚕不同发育时期中肠组织的石蜡切片,发现幼虫中肠细胞在进入蛹变态期发生了多次凋亡与再生的过程,在上蔟3~4d、上蔟7~8d、上蔟12d~蛾期都形成了新的中肠上皮细胞,这些新的中肠上皮细胞可能是由再生细胞分化更新而来的。对家蚕中肠组织中细胞凋亡基因(Caspase-1、BmDredd)与自噬基因(Atg1、Atg13)表达模式的检测结果显示,Caspase-1、BmDredd在上蔟2d、7d、12d的表达量均降低,Atg1、Atg13在上蔟7d、9d、12d的表达量均降低,表明在家蚕的这些变态发育时期,其中肠细胞的凋亡受到了抑制,与切片观察新的中肠上皮细胞形成时期基本一致。研究结果呈现了家蚕中肠在蛹变态时期的发育变化过程,说明家蚕幼虫的中肠在蛹发育变态过程中并未彻底消亡,成虫的中肠是幼虫中肠在蛹变态时期经过多次消亡与再生过程发育而来的。

家蚕响应微孢子虫感染的可变剪接事件分析

【目的】家蚕微孢子虫(Nosema bombycis)感染引发的微粒子病是影响蚕业发展的重要病害。为了揭示可变剪接(AS)基因在家蚕响应微孢子虫感染中的作用,对其中肠内的AS事件进行分析。【方法】利用Illumina Hiseq TM 4000测序平台,对健康家蚕(对照组)和被微孢子虫感染的家蚕中肠组织进行转录组测序。使用rMATS软件对样品中的AS事件与差异剪接基因(DSGs)进行鉴定,并对DSGs进行GO富集和KEGG信号通路分析。【结果】在对照组和感染组中分别检测到5346个和4992个AS事件,两组的AS事件类型都以外显子跳跃(SE)事件为主,差异分析发现了25个显著的DSGs。GO富集分析表明,DSGs主要富集在21个条目,其中以细胞过程、物质代谢、结合、催化活性的基因数量较多;KEGG信号通路分析显示,DSGs富集数较多的是信号传导、免疫系统、多糖生物合成与降解、能量代谢等通路。【结论】家蚕中肠组织存在大量AS事件,在微孢子虫感染过程中存在25个DSGs,其功能涉及新陈代谢和细胞免疫等。

刻点血蜱成蜱中肠菌群结构的分析

旨在探明雌、雄刻点血蜱中肠菌群结构特征及其差异。从新疆沙湾市绵羊体表采集刻点血蜱雌、雄蜱,无菌条件下收集雌、雄蜱中肠内容物,提取各样本细菌总DNA,PCR扩增细菌16S rDNA V3-V4区,运用Illiumina NovaSeq高通量双末端测序,对数据进行拼接和过滤,扩增子序列变异(ASVs)降噪与物种注释后,对比分析雌、雄蜱中肠菌群结构的组成及差异。结果:雌蜱中肠菌群多样性高于雄蜱;在门水平上,变形菌门、厚壁菌门、异常球菌门、拟杆菌门、放线菌门在雌、雄蜱中肠内相对丰度较高,其中变形菌门相对丰度最高,为2个样本的优势菌门,且变形菌门在雄蜱中肠内的含量大于雌蜱;在属水平上,Schlegelella、不动杆菌属、拟杆菌属、乳杆菌属、短波单胞菌属、罗姆布茨菌属等在雌、雄蜱中肠内的相对丰度较高,其中Schlegelella的丰度最高,且在雌蜱(41.7%)中的含量高于雄蜱(0.8%);注释到种水平且2个样本共有的菌种包括:西尔瓦诺斯亚栖热菌、鲍曼不动杆菌、柯克斯氏体共生菌、肠乳杆菌、长双歧杆菌、巴氏杆菌拟杆菌等。本研究表明,刻点血蜱雌、雄蜱中肠菌群结构较为相似,但各细菌在不同分类级别上的相对丰度差异较大,这可能与雌、雄蜱吸血及生理特性不同有关。

蜱传病原体的危害及其与媒介蜱相互作用的研究进展

蜱作为一大类传播媒介,可传播多种病原体,如嗜吞噬细胞无形体和伯氏疏螺旋体,造成人和动物的无形体病和莱姆病,危害公共卫生安全。然而,化学药物的滥用导致蜱及蜱传病原体产生耐药性,而抗蜱疫苗存在一定的局限性,亟需找到有效且绿色安全的蜱和蜱传病的防控方法。一些病原体在传播过程中逐渐进化出特定机制,如调控蜱细胞凋亡、免疫逃避等促进其在蜱体内的生长发育;而蜱自身也产生了某些应对机制来抵御或协同传播病原体,如分泌外泌体小囊泡协同传播病毒,促进自身受感染细胞凋亡,分泌唾液蛋白调节宿主补体途径,形成肠道屏障等。本文对蜱传病原体的类型和危害、病原体经蜱唾液腺传播的相互作用机制以及蜱中肠屏障和肠道菌群与病原体增殖的相互关系共3个方面进行综述,希望能为后续防控蜱和蜱传病及抗蜱药物的相关研究提供参考。

单宁酸对豌豆蚜谷胱甘肽-S-转移酶活性与基因表达的影响

本研究通过测定单宁酸(2 g·L^(-1))处理豌豆蚜(Acyrthosiphon pisum) 48 h后体内谷胱甘肽-S-转移酶(GST)活性以及不同组织GST基因转录水平的变化,以明确单宁酸对GST活性以及基因表达的影响。结果表明:豌豆蚜取食单宁酸(2 g·L^(-1)) 48 h后,GST活性下降。相比不处理对照,经单宁酸处理后,豌豆蚜头部有7个GST基因上调表达,其中ApGST104、ApGSTX1上调表达3倍左右;胸部有10个GST基因上调表达,其中ApGSTD6上调表达6.4倍;腹部有10个GST基因上调表达,其中ApGST101、ApGST105上调5倍左右;中肠有9个GST基因上调表达,其中ApPGST105上调表达3.2倍。从结果可以看出,单宁酸对豌豆蚜GST基因的表达产生了影响,部分GST基因显著上调表达(P <0.05),表明GST基因可能在豌豆蚜对单宁酸的代谢中发挥重要的作用。

Histopathological Effects of the Protein Toxin from Xenorhabdus nematophila on the Midgut of Helicoverpa armigera

Xenorhabdus nematophila HB310, which is highly virulent for many insects, is symbiotic with Steinernema carpocapsae HB310. Toxin II was obtained using methods such as salting out and native-PAGE from the cells of X. nematophila HB310. The histopathology of toxin II on H. armigera larvae was studied by dissecting an olefin slice of the midgut. The symptoms showed that the histopathology of the H. armigera midgut was similar to that of other novel midgut-active toxins such as the δ-endotoxins from Bacillus thuringiensis, as well as Tca from Photorhabdus luminescens W14. The midgut tissues of H. armigera fourth-instar larvae began to transform after the oral intake of the toxin Ⅱ over 6 h. First, the anterior region of the peritrophic membrane （PM） began to degrade followed by the elongation of the columnar cells. The epithelium decomposed gradually, and the midgut tissues were either loose or disordered. The PM disappeared after 12 h but reappeared after 72 h following transient or sublethal exposure to the toxin Ⅱ. Toxin Ⅱ also directly destroyed in vitro PMs of H. armigera.

A Study on the Activity of Carboxylesterase and the Differential Expression of Its Gene in the Midguts of Bombyx mori Resistant to BmDNV-Z

This study was to discuss the relationship among the change in the activity of Bombyx mori carboxylesterase （BmCarE） in the midguts, the differential expression of BmCarE gene （bmcare） in the midguts, and the ability of Bombyx mori resistant to densonucleosis virus （BmDNV）, and to elucidate the molecular mechanism of resistance to BmDNV-Z. With two silkworm strains, HUABA, which is susceptible to BmDNV-Z, and BC8 （a near isogenic line of HUABA）, which is completely resistant to the same virus, as materials, the activity of BmCarE in the midgut was determined by Bio-Tek Synergy, and the differential expression of bmcare between the two strains was investigated by real-time fluorescence quantitative PCR, both at 12, 36, and 72 h post oral inoculation of the two strains with virus （hereafter referred as inoculation）. While the activity of BmCarE in the midguts of BC8 inoculation group at 12 h post inoculation was higher than that in the BC8 control group, the HUABA inoculated group, and the HUABA control group by 3.28, 2.26, and 3.02 times, respectively, with the difference being highly significant （P 〈 0.01）, there was no statistical difference among the other groups. The relative expression level of bmcare in the midguts of BC8 inoculation group at 12 h post inoculation was higher than that in the BC8 control group, the HUABA inoculation group, and the HUABA control group by 17.714, 21.76, and 15.09 times, respectively, with the difference being highly significant （P 〈 0.01）, and there was no statistical difference among other groups. The elevation of BmCarE activity and expression level of bmcare in the resistant strain at 12 h post inoculation may relate to the resistant gene （nsd/nsd） and the stimulation of BmDNV-Z. The molecular basis for the elevation of BmCarE activity in the resistant strain BC8 may be the change in the expression level of bmcare.

Intrauterine midgut volvulus without malrotation:Diagnosis from the 'coffee bean sign'

Fetal midgut volvulus is quite rare, and most cases are associated with abnormalities of intestinal rotation or fixation. We report a case of midgut volvulus without malrotation, associated with a meconium pellet, during the gestation period. This 2.79 kg, 33-wk infant was born via a spontaneous vaginal delivery caused by preterm labor. Prenatal ultrasound showed dilated bowel loops with the appearance of a 'coffee bean sign'. This patient had an unusual presentation with a distended abdomen showing skin discoloration. An emergency laparotomy revealed a midgut volvulus and a twisted small bowel, caused by complicated meconium ileus. Such nonspecific prenatal radiological signs and a low index of suspicion of a volvulus during gestation might delay appropriate surgical management and result in ischemic necrosis of the bowel. Preterm labor, specific prenatal sonographic findings (for example, the coffee bean sign) and bluish discoloration of the abdominal wall could suggest intrauterine midgut volvulus requiring prompt surgical intervention.

Effects of inhibitors on the protease profiles and degradation of activated Cry toxins in larval midgut juices of Cnaphalocrocis medinalis (Lepidoptera:Pyralidae)

Midgut juice plays an important role in food digestion and detoxification in insects.In order to understand the potential of midgut juice of Cnaphalocrocis medinalis(Guenée)to degrade Bt proteins,the enzymatic activity of midgut juice and its degradation of Bt proteins(Cry2A,Cry1C,Cry1Aa,and Cry1Ac)were evaluated in this study through protease inhibitor treatments.The activities of total protease in midgut juices were significantly inhibited by phenylmethylsulfonyl fluoride(PMSF),tosyl-L-lysine chloromethyl ketone(TLCK),pepstatin A and leupeptin.The enzymatic activity of chymotrypsin was significantly inhibited by PMSF,and enzymatic activity of trypsin was significantly inhibited by ethylenediaminetetraacetic acid(EDTA),PMSF,tosyl phenylalanine chloromethyl ketone(TPCK),TLCK and trans-epoxysuccinyl-L-leucylamido-(4-guanidino)butane(E-64).EDTA could significantly inhibit the degradation of Cry2A by C.medinalis.EDTA,PMSF,TPCK,and TLCK could inhibit the degradation of Cry1C and Cry1Aa.EDTA,PMSF,TPCK,TLCK,and E-64 could inhibit the degradation of Cry1Ac.Our results indicated that some protease inhibitors hindered various enzymatic activities in the larval midgut of C.medinalis,which may reduce the insect’s ability to degrade Bt toxins.These findings may aid the application of protease inhibitors in the management of this insect pest in the future.

Intestinal obstruction in pregnancy with reverse rotation of the midgut:A case report

BACKGROUND Reverse rotation of the midgut is a rare type of intestinal malrotation.Volvulus of the right colon or entire midgut,stenosis of the transverse colon and obstruction of the duodenojejunal junction are common complications of reverse rotation.In this study,we report the first case of intestinal obstruction associated with reverse rotation in pregnancy.CASE SUMMARY A 31-year-old woman at 362+wk gestation presented to the emergency department with progressive abdominal cramping,nausea and bilious vomiting.Abdominal ultrasound scanning showed dilatation of the bowel.Computed tomography scanning revealed features of reverse rotation of the midgut with intestinal volvulus.After consultation with the obstetrician,the pregnancy was terminated and exploratory abdominal surgery was performed.Intra-operatively,it was found that the mesentery of the colon and small intestine was insufficiently attached.The right colon and the small intestinal mesentery was twisted,and intestinal necrosis was observed.The duodenum and duodenojejunal junction were curved in front of the transverse colon,and the transverse colon passed through the tunnel behind the mesenteric root.Intestinal reverse rotation with volvulus was confirmed.The necrotic intestine was resected and small intestine mesenteric reconstruction was performed.The patient recovered after surgery.After leaving the hospital,the patient and her daughter remained well during an 8-month follow-up period.CONCLUSION We report the diagnosis,treatment and etiology of a pregnant patient with intestinal obstruction due to reverse rotation of the midgut.For similar cases,appropriate diagnosis and treatment should be carried out according to the condition of the fetus and pregnant woman.

Midgut volvulus due to jejunal diverticula:A case report

Jejunal diverticulosis is uncommon and often asymptomatic.It can produce significant complications,and some complications are potentially life threatening and require early surgical treatment,such as obstruction,hemorrhage and perforation.There is no consensus on the management of this disease.Only a few cases of jejunal diverticulosis with midgut volvulus have been reported.We herein report a case of 57-year-old woman with jejunal diverticulosis causing small bowel volvulus who complained of intermittent upper abdominal pin-prick for 5 years that eventually progressed to a complete obstruction.The computed tomography scans revealed a mesenteric vessel "whirlpool" and laparotomy showed midgut volvulus secondary to jejunal diverticula.This case highlights jejunal diverticulosis causing small bowel volvulus as an uncommon mechanism of small bowel obstruction,which should be included in the differential diagnosis of small bowel obstruction.

Use of Ultrastructuke and DNA Hybridization to Detect Replication of the Nuclear Polyhedrosis Virus in Midgut Cells of Homologous Host

It was controversial issue if nuclear polyhedrosis virus(NPV) could replicate in midgut cells of host larvae from Lepidoptera by now.The replication of Mythimna separata NPV(MsNPV) in M.separata larvae midgut cells was studied by ultrastructural and DNA hybridized techniques.The paper demonstrated that the MsNPV could neither infect midgut cell nor replicate in midgut cell of homologous host.Therefore MsNPV virions released from the virial occlusion bodies were considered as direct penetration though the intercellular spaces of midgut cells to hemocoel of the host larvae.

The Midgut Bacterial Flora of Laboratory-Reared Hard Ticks, Haemaphysalis longicornis, Hyalomma asiaticum, and Rhipicephalus haemaphysaloides

Ixodid ticks play an important role in the transmission of a variety of zoonoses of viral, bacterial and protozoan origin, and they also harbor a wealth of microorganisms. To gain more detailed insights into the potential interactions between bacterial flora and tick-borne pathogens, we investigated the midgut bacterial flora of laboratory-reared Haemaphysalis longicornis, Hyalomma asiaticum and Rhipicephalus haemaphysaloides. Based on morphological, biochemical, and 16 S rDNA sequencing results, we identified 15 species belonging to 12 genera in the midgut of the three ticks. The bacterial communities were similar to those found in other studies of hematophagous arthropods. Kocuria sp. was the most frequently isolated species and its 16 S rDNA gene sequence was very similar to Kocuria koreensis P31 T. To our knowledge, this is the first report of the bacterial flora of tick midguts and the results show that there were many different bacterial species in each tick species. Among the most common genera, there may have been a novel species in the genus Kocuria. The results might be the first step for looking for different aspects of the pathogen and tick interaction.

A Case Report of Adult Patent Vitellointestinal Duct Sac and Midgut Volvulus

Midgut volvulus is a clinical rare condition which appears as recurrent intermittent abdominal pain after consumption of food with intermittent colicky pain and sometimes with completely asymptomatic period. This gut twist may result in complications such as ischemia, obstruction, hemorrhage, or perforation. In the yolk sac during the third week of intrauterine life, there is normal communication with intraembryonic gut. During development proceeds, this communication gets thinner into a tube known as the vitellointestinal duct. Vitellointestinal duct usually becomes obliterated before eighth week of intrauterine life. In about 2% of people this duct persists and gives rise to a group of anomalies such as Meckel’s diverticulum is the commonest and complete patency of the duct is the rarest. Here we present the case of a 34-year-old male who presented with both conditions.

基于中肠代谢组学意大利蜜蜂工蜂枣花病的发病机理研究

【目的】利用代谢组学分析患枣花病意大利蜜蜂Apis mellifera ligustica工蜂中肠内代谢物变化,挖掘出与蜜蜂枣花病相关的重要代谢通路,旨在揭示蜜蜂枣花病发病机制,为枣花病靶向药物的研发提供理论依据。【方法】分别利用液相色谱-质谱联用(liquid chromatography-mass spectrometry,LC-MS)和气相色谱-质谱联用(gas chromatography-mass spectrometry,GC-MS)技术对患枣花病和健康意大利蜜蜂工蜂进行中肠非靶向代谢组检测;通过主成分分析(principal component analysis,PCA)和正交偏最小二乘法判别分析(orthogonal partial least squares discriminant analysis,OPLS-DA),以变量投影重要性(variable projection importance,VIP)>1.0,差异倍数(fold change,FC)>2.0和P<0.05为标准筛选差异代谢物,并对其进行KEGG注释和通路富集;利用生化方法测定意大利蜜蜂工蜂中肠中超氧化物歧化酶(superoxide dismutase,SOD)和过氧化氢酶(catalase,CAT)的活性,并通过qRT-PCR测定抗氧化基因Sod1,Sod 2和CAT及免疫基因Defensin,Hymenoptaecin,Apidaecin和Abaecin在中肠内的表达量。【结果】基于LC-MS代谢组检测,正离子和负离子模式下分别获得患枣花病和健康意大利蜜蜂工蜂间差异代谢物49和43种,其中分别有33和30种能够在HMDB和KEGG数据库中鉴定到。基于GC-MS代谢组检测,患枣花病和健康意大利蜜蜂工蜂间筛选到22种挥发性差异代谢物,其中11种能够在HMDB和KEGG数据库中鉴定到。与健康意大利蜜蜂工蜂相比,患枣花病意大利蜜蜂工蜂中肠内经鉴定的73种差异代谢物中,28种含量上升,45种含量下降;其中,京尼平苷酸、吲哚-3-乙酸、喹啉和棉子糖在患枣花病意大利蜜蜂工蜂中肠内大量积累,而乌索酸、L-苏糖酸、葡萄糖酸、D-半乳糖酸、苏糖酸和芦丁的含量下降最为明显。KEGG代谢通路富集分析结果表明,患枣花病和健康意大利蜜蜂工蜂间差异代谢物显著富集在抗坏血酸和醛酸代谢、半乳糖代谢及丁酸甲酯代谢这3条碳水化合物代谢通路。酶活性测定及qRT-PCR结果显示,与健康意大利蜜蜂工蜂相比,患枣花病意大利蜜蜂工蜂中肠中SOD和CAT酶活显著降低,Sod1,Sod2,CAT,Defensin,Hymenoptaecin和Apidaecin的表达量均呈下调趋势。【结论】利用LC-MS和GC-MS非靶向代谢组学均能够有效地分析枣花病影响下蜜蜂中肠内代谢物的变化差异。研究结果表明,意大利蜜蜂采集枣花后其中肠内碳水化合物代谢发生异常,引起肠道抗氧化和免疫能力显著下降,推测肠道功能障碍是导致蜜蜂死亡的主要原因。该研究为蜜蜂枣花病的发病机理提供了新见解。

取食臭椿不同部位对沟眶象和臭椿沟眶象成虫消化解毒酶的影响

沟眶象Eucryptorrhynchus scrobiculatus和臭椿沟眶象E.brandti是取食单一寄主臭椿Ailanthus altissima不同部位的钻蛀性害虫。二者成虫羽化后交配之前均需补充营养,且取食臭椿不同部位(叶柄、1年生枝、2~3年生枝、主干)对其雌成虫生殖系统发育的影响差异显著。就臭椿沟眶象雌成虫而言,只有取食主干才能够产卵;而对沟眶象雌成虫来说,则只有取食2~3年生枝的无法产卵。本研究使用臭椿的4种不同部位(叶柄、1年生枝、2~3年生枝、主干)饲喂这两种象甲成虫,利用ELISA试剂盒测定两种象甲的3种解毒酶(谷胱甘肽转移酶、羧酸酯酶和细胞色素P450)和3种消化酶(胰蛋白酶、淀粉酶、脂肪酶)的酶活性。结果表明,两种象甲中后肠的6种酶活性在取食不同寄主部位后发生显著性差异。其中,臭椿沟眶象雌成虫取食主干显著降低其中后肠的CarE酶活性,沟眶象雌成虫取食2~3年生枝能显著提高中后肠的CarE酶活性,同时降低中后肠AMY酶活性。本文明确了寄主植物不同部位对这两种象甲成虫中后肠消化解毒酶活性的影响,分析了两种象甲初羽化雌成虫补充营养造成生殖系统发育差异的原因,对后续这两种象甲消化解毒酶相关研究有一定参考价值。

取食Cry3Aa蛋白后黄曲条跳甲成虫中肠组织的病理变化

为明确Cry3Aa蛋白对黄曲条跳甲成虫的致死效果及作用机理,采用浸叶法测定了黄曲条跳甲成虫取食Cry3Aa蛋白后的死亡情况,并利用透射电镜观察了Cry3Aa蛋白处理后成虫中肠组织的病理学变化。结果显示,取食浓度为2 mg/mL的Cry3Aa蛋白6 d和12 d后黄曲条跳甲成虫的死亡率分别为33.33%和77.78%;透射电镜观察发现,蛋白处理后成虫中肠发生了明显的病理变化,并且随着时间的延长,病理变化更加明显,主要表现为:柱状细胞变形、细胞间隙增大、微绒毛缩短并肿胀、线粒体变形、内质网肿胀。本研究表明黄曲条跳甲成虫中肠是Cry3Aa蛋白的重要作用部位,研究结果为揭示Cry3Aa蛋白对黄曲条跳甲成虫的作用机理奠定了基础。