Sub-Lethal Effects of Fenvalerate on the Development, Fecundity, and Juvenile Hormone Esterase Activity of Diamondback Moth, Plutella xylostella (L.)

The toxicities of fenvalerate （20% EC） to the 3rd instar larvae of diamondback moth （DBM）, Plutella xylostella （L.）, reared on three host plants viz., radish, oilseed rape, and cabbage were tested. The LC50 values of fenvalerate to the 3rd instar larvae of DBM varied with host plants, however, there wasn＇t any significant difference among them （P〉 0.05）. Similarly, DBM fed on three host plants had same pupal weight, pupal period, pupation rate, adult emergence rate, female ratio, and fecundity. The activity of juvenile hormone esterase （JHE, EC 3.1.1.1） in the 3rd instar larvae of DMB did not significantly vary with host plants, either. These suggested that DBM had similar fitness on the three host plant species. When fed on the host plants pretreated with fenvalerate at the concentrations equivalent to LC20, LC50 and LC50, the pupation rate, pupal weight, adult emergence rate, female ratio, fecundity, and JHE activity of the tested insects were declined as compared with insects in control treatments fed on the same host plant species. Furthermore, the pupal period of the tested insects was extended after fenvalerate treatment. The decrease in JHE activity after fenvalerate treatment in the tested insects could partly explain the changes in the mentioned growth parameters. Whether the role of fenvalerate in the inhibition of JHE activity could serve as a new way to control DBM needs further investigation.

In the monarch butterfly the juvenile hormone effect upon immune response depends on the immune marker and is sex dependent

In insects, juvenile hormone (JH) decreases or has any effect upon the phenoloxidase (PO) activity, and favors or decreases the Antimicrobial Peptides (AMPs) expression. Although there is no information about the differential effect of such hormone, two possibilities are that it depends on (a) the immune marker recorded and (b) sexual differences. Here, three commonly used immune markers, Phenoloxidase (PO), hydrogen peroxide (H2O2), and lytic activity, were measured 3, 6 and 24 hours after administration of methoprene (JHa, an analog of juvenile hormone) in male and female monarch butterflies (Danaus plexippus). At 3 and 6 h post-JHa administration, the PO activity increased in females but it only increased at 3 h in males, whereas H2O2 levels increased only in females at 3 h. For the remaining times the JHa had a null effect on POand H2O2. On the other hand, the JHa had a null effect for lytic activity in both sexes at 3, 6 and 24 h. To our knowledge, this is the first report of a positive effect of a JHa onPOand H2O2 and suggests that this effect is sex dependent.

Identification and developmental expression of putative gene encoding juvenile hormone esterase(CpJHE-like) in codling moth, Cydia pomonella(L.)

Juvenile hormone esterase(JHE) is a key enzyme for insects,playing an important role in the regulation of insect growth,development,diapause and reproduction.We identified a complete putative JHE of Cydia pomonella(CpJHE-like) which is comprised of a 1 761 bp coding sequence(CDS) encoding 587 amino acid residues from the transcriptome data.The deduced protein sequence of CpJHE-like showed the highest identity of 60.44% with the Adoxophyes honmai JHE(AhJHE) and the minimal identity of 25.81% with Aedes aegypti JHE(AaJHE).CpJHE-like exhibited all the seven typical motifs of the functional JHEs and had the highly consistent tertiary structure with Manduca sexta JHE(MsJHE).Phylogenetic analysis showed that the CpJHE-like was close to two JHEs from the family Tortricidae.The CpJHE-like transcript level take a leap in the 3-day-old fifth instar larva,increased about 300-fold compared to the basal level.Tissue-specific expression profile showed that the CpJHE-like transcript was expressed mainly in the fat body.This study indicates that the CpJHE-like is the functional JHE,which may play vital roles in the development and reproduction of C.pomonella.

Juvenile hormone induces reproduction via miR-1175-3p in the red imported fire ant, Solenopsis invicta

Juvenile hormone(JH)acts in the regulation of caste differentiation between queens and workers(i.e.,with or without reproductive capacity)during vitellin synthesis and oogenesis in social insects.However,the regulatory mechanisms have not yet been elucidated.Here,we identified a highly expressed microRNA(miRNA),miR-1175-3p,in the red imported fire ant,Solenopsis invicta.We found that miR-1175-3p is prominently present in the fat bodies and ovaries of workers.Furthermore,miR-1175-3p interacts with its target gene,broad-complex core(Br-C),in the fat bodies.By utilizing miR-1175-3p agomir,we successfully suppressed the expression of the Br-C protein in queens,resulting in reduced vitellogenin expression,fewer eggs,and poorly developed ovaries.Conversely,decreasing miR-1175-3p levels led to the increased expression of Br-C and vitellogenin in workers,triggering the“re-development”of the ovaries.Moreover,when queens were fed with JH,the expression of miR-1175-3p decreased,whereas the expression of vitellogenin-2 and vitellogenin-3 increased.Notably,the suppression of fertility in queens caused by treatment with agomir miR-1175-3p was completely rescued by the increased vitellogenin expression induced by being fed with JH.These results suggest the critical role of miR-1175-3p in JH-regulated reproduction,shedding light on the molecular mechanism underlying miRNA-mediated fecundity in social insects and providing a novel strategy for managing S.invicta.

Juvenile hormone acts on male accessory gland function via regulating L-asparaginase expression and triacylglycerol mobilization in Aedes aegypti

Hormones control the reproductive development of Aedes aegypti mosquitoes.The adult male reproductive process and mating behavior require adequate nutrients and energy.Understanding the molecular mechanism linking hormones,energy metabolism,and reproduction in male mosquitoes is important.In this study,we found that the size of the male accessory gland,an essential part of the male reproductive system,gradually increased after eclosion.However,it was significantly reduced in male mosquitoes deficient in methoprene-tolerant(Met),the receptor of juvenile hormone.Likewise,egg hatchability of females that mated with Met-depleted males showed the same downward trend.The mRNA level of the gene encoding accessory gland protein,l-asparaginase(ASNase),was reduced in Met dsRNA-treated males.Electrophoretic mobility shift assay and quantitative reverse transcription-PCR results revealed that Met was capable of binding directly to the promoter of ASNase and activated its transcription.RNA interference of ASNase in males resulted in the reduction of egg hatchability of the females with which they mated.These results showed that Met influenced the fecundity of male mosquitoes by directly upregulating the expression of the ASNase gene.Moreover,the levels of triacylglycerol and the sizes of lipid droplets were decreased by 72-78 h after eclosion in the fat body cells,whereas both of them increased in Met-depleted male mosquitoes,indicating that Met knockdown reduced lipid catabolism.These data demonstrate that Met might influence the egg hatchability of females by regulating lipid metabolism and the development of the male accessory gland in male mosquitoes.

Methoprene does not affect juvenile hormone titers in honey bee （Apis mellifera） workers

Methoprene, a juvenile hormone （JH） analog, is a widely used insecticide that also accelerates behavioral development in honey bees （Apis mellifera）. JH regulates the transition from nursing to foraging in adult worker bees, and treatment with JH or methoprene have both been shown to induce precocious foraging. To determine how methoprene changes honey bee behavior, we compared JH titers ofmethoprene-treated and untreated bees. Behavioral observations confirmed that methoprene treatment significantly increased the number of precocious foragers in 3 out of 4 colonies. In only 1 out of 4 colonies, however, was there a significant difference in JH titers between the methoprene- treated and control bees. Further, in all 4 colonies, there was no significant differences in JH titers between precocious and normal-aged foragers. These results suggest that methoprene did not directly affect the endogenous JH secreted by corpora allata. Because methoprene caused early foraging without changing workers＇ JH titers, we conclude that methoprene most likely acts directly on the JH receptors as a substitute for JH.

The biosynthesis of alarm pheromone in the wheat aphid Rhopalosiphum padi is regulated by hormones via fatty acid metabolism

Aphids are major insect pests in agriculture and forestry worldwide.Following attacks by natural enemies,many aphids release an alarm pheromone to protect their population.In most aphids,the main component of the aphid alarm pheromone(AAP)is the sesquiterpene hydrocarbon(E)-β-farnesene(EβF).However,the mechanisms behind its biosynthesis and regulation remain poorly understood.In this study,we used the bird cherry–oat aphid Rhopalosiphum padi,which is an important wheat aphid,to investigate the regulatory mechanisms of EβF biosynthesis.Our results showed that EβF biosynthesis occurs during the mature embryo period and the molting period of the 1st-and 2nd-instar nymphs.Triglycerides provide the prerequisite material for EβF production and release.Based on transcriptome sequencing,RNAi analysis,hormone treatments,and quantitative measurements,we found that the biosynthesis of EβF utilizes acetyl coenzyme A produced from fatty acid degradation,which can be suppressed by juvenile hormone but it is promoted by 20-hydroxyecdysone through the modulation of fatty acid metabolism.This is the first systemic study on the modulation of EβF production in aphids.The results of our study provide insights into the molecular regulatory mechanisms of AAP biosynthesis,as well as valuable information for designing potential aphid control strategies.

Cloning and structural characterization of juvenile hormone diol kinase in Spodoptera litura

Juvenile hormone （JH） is one of the key insect hormones that regulate metamorphosis. Juvenile hormone diol kinase （JHDK） is an enzyme involved in JH metabolism and catalyzes JH diol to form a polar end product, JH diol phosphate that has no JH activity. In this study, a JHDK complementary DNA （cDNA） was cloned from Spodoptera litura and the structure and expression of the gene was characterized. The cDNA was 714 base pairs in length and encoded a protein of 183 amino acids with a molecular mass of 21 kDa and an isoelectric point of 4.55. Based on the structure, three putative calcium binding motifs and guanosine triphosphate-binding motifs were predicted in the protein. Modeling of the 3-D structure showed that the protein consisted of eight α-helixes linked with loops, with no β-sheets. The gene was expressed in the epidermis, fat body and midgut of fifth and sixth instar larvae. The expression level in the epidermis was lower than in the fat body and midgut. The gene was expressed at higher levels at the early stages than in the later stages of fifth and sixth instar midgut and fat body. The results suggest that this gene may be involved in the regulation of the JH titer in larvae ofS. litura.

Juvenile hormone signaling-a mini review

Since it was first postulated by Wigglesworth in 1934, juvenile hormone (JH) is considered a status quo hormone in insects because it prevents metamorphosis that is initiated by the molting hormone 20-hydroxyecdysone (20E). During the last decade, significant advances have been made regarding JH signaling. First, the bHLH-PAS transcription factor Met/Gce was identified as the JH intracellular receptor. In the presence of JH, with the assistance of Hsp83, and through physical association with a bHLH?PAS transcriptional co-activator, Met/Gce enters the nucleus and binds to E-box-like motifs in promoter regions of JH primary?response genes for inducing gene expression. Second, the zinc finger transcription factor Kr-hl was identified as the anti-metamorphic factor which transduces JH signaling. Via Kr-hl binding sites, Kr-hl represses expression of 20E primary?response genes (i.e. Bi\ E93 and E5) to prevent 20E-induced metamorphosis. Third, through the intracellular signaling, JH promotes differ ent aspects of female reproduction. Nevertheless, this action varies greatly from species to species. Last, a hypothetical JH membrane receptor has been predicted to be either a GPCR or a tyrosine kinase receptor. In future, it will be a great challenge to understand how the JH intracellular receptor Met/Gce and the yet unidentified JH membrane receptor coordinate to regulate metamorphosis and reproduction in insects.

Expression of juvenile hormone acid O-methyltransferase and juvenile hormone synthesis in Blattella germanica

Juvenile hormone （JH）, a sesquiterpenoid synthetized by the insect corpora allata （CA）, plays critical roles in metamorphosis and reproduction. Penultimate or last step of JH synthesis is catalyzed by juvenile hormone acid O-methyltransferase （JHAMT）. Here we report the cloning and expression analysis of the JHAMT orthologue in the cockroach, Blattella germanica （L.） （BgJHAMT）. BgJHAMT is mainly expressed in CA, with only expression traces in ovary. Three different isoforms, differing in the 3＇-UTR sequence, were identified. Isoform A shows between 35 and 65 times higher expression than B and C in CA from penultimate nymphal instar and adult females. RNAi-triggered knock down of BgJHAMT produces a dramatic reduction of JH synthesis, concomitant with a decrease of fat body viteUogenin expression and basal follicle length. BgJHAMT mRNA levels in CA of females along the gonadotrophic cycle parallel, with a slight advancement, JH synthesis profile. BgJHAMT mRNA levels were reduced in starved females and in females in which we reduced nutritional signaling by knocking down insulin receptor and target of rapamycin （TOR）. Results show that conditions that modify JH synthesis in adult B. germanica females show parallel changes of BgJHAMT mRNA levels and that the JH-specifie branch of the JH synthesis pathway is regulated in the same way as the mevalonate branch. Furthermore, we demonstrate that nutrition and its signaling through the insulin receptor and TOR pathways are essential for activating BgJHAMT expression, which suggests that this enzyme can be a checkpoint for the regulation of JH production in relation to nutritional status.

Dual roles of juvenile hormone signaling during early oogenesis in Drosophila

Juvenile hormone(JH)signaling plays crucial roles in insect metamorphosis and reproduction.Function of JH signaling in germline stem cells(GSCs)remains largely unknown.Here,we found that the number of GSCs significantly declined in the ovaries of Met,Gee and JHAMT mutants.Then we inhibited JH signaling in selected cell types of ovaries by expressing Met and Gee or Kr-hl double-stranded RNAs(dsRNAs)using different Gal4 drivers.Blocking of JH signaling in muscle cells has no effect on GSC numbers.Blocking of JH signaling in cap cells reduced GSCs cells.Inductive expression of Met and Gee dsRNA but not Kr-hl by Nos-Gal4 increased GSC cells.These results indicate that JH signaling plays an important role in GSC maintenance.

Juvenile hormone membrane signaling phosphorylates USP and thus potentiates 20-hydroxyecdysone action in Drosophila

Juvenile hormone(JH) and 20-hydroxyecdysone(20 E) coordinately regulate development and metamorphosis in insects. Two JH intracellular receptors, methoprene-tolerant(Met) and germ-cell expressed(Gce), have been identified in the fruit fly Drosophila melanogaster. To investigate JH membrane signaling pathway without the interference from JH intracellular signaling, we characterized phosphoproteome profiles of the Met gce double mutant in the absence or presence of JH in both chronic and acute phases.Functioning through a potential receptor tyrosine kinase and phospholipase C pathway, JH membrane signaling activated protein kinase C(PKC) which phosphorylated ultraspiracle(USP) at Ser35, the PKC phosphorylation site required for the maximal action of 20 E through its nuclear receptor complex Ec RUSP. The usp;mutant, in which Ser was replaced with Ala at position 35 by genome editing, showed decreased expression of Halloween genes that are responsible for ecdysone biosynthesis and thus attenuated 20 E signaling that delayed developmental timing. The usp;mutant also showed lower Yorkie activity that reduced body size. Altogether, JH membrane signaling phosphorylates USP at Ser35 and thus potentiates 20 E action that regulates the normal fly development. This study helps better understand the complex JH signaling network.

Juvenile hormone regulates photoperiod-mediated male reproductive diapause via the methoprene-tolerant gene in the ladybeetle Harmonia axyridis

Juvenile hormone (JH) absence induces photoperiod-mediated reproductive diapause, which is characterized by reproductive cessation. Although the role of methoprene-tolerant (Met)-mediated JH signaling in photoperiod-mediated female reproduction has been well documented, its role in male reproduction remains unclear. In this study, we investigated the role of JH in regulating photoperiod-mediated development of the male internal reproductive system (IRS) in the predatory ladybeetle Harmonia axyridis (Pallas). In a previous study, we found that adult male H. axyridis reared under either a short-day (SD) or long-day (LD) photoperiod had obvious differences in IRS development, but we were unable to identify the regulators of male reproductive diapause. In this study, we found that beetles reared under an SD photoperiod had significantly lower JH titer and a relatively undeveloped male IRS compared with those reared under an LD photoperiod. Additionally, application of the JH analog (JHA) methoprene promoted IRS development. Furthermore, Met knockdown strongly blocked JH signaling in males reared under the LD photoperiod, thereby slowing IRS development. Moreover, exogenous JHA did not reverse the suppressed development of the male IRS caused by Met knockdown. These results indicate that photoperiod regulates male IRS development in H. axyridis through a conserved Met-dependent JH signaling pathway.

Effects of thyrotropin-releasing hormone on severe head injury:A preliminary clinical trial

Objective: To evaluate the effects of thyorotropin-releasing hormone (TRH ) on severe head injury.Methods: Eighty--seven severely head injured patients with a Glasgow Coma Scale (GCS ) score of & or less wererandomized into TRH--treated and saline control groups. In TRH treated group. the treatment was started with abolus injection of 0. 2 mg/kg followed by continuous infusion for 2 hours at 0. 2 mg/kg/h. Such treatment wasgiven once a day for 4 times. The patients in control group were given the equivalent normal saline with the samemethod. Results: TRH, administered intravenously after head injury. promoted the recovery of consciousness andGCS score, alleviated the traumatic brain edema, controlled and lowered the intracranial pressure. decreased thelevel of lipid superoxides, decreased the mortality rate. and improved the life quality of the survivals. Nocomplications or adverse and toxic effects were noted during the course of TRH treatment. Conclusion: TRH hasbeneficial effects on patients with severe head injury.

昆虫激素对家蚕不同组织β-N-乙酰葡萄糖苷酶活性的影响

【目的】研究蜕皮激素20E和保幼激素JH处理对家蚕5龄幼虫不同组织β-N-乙酰葡萄糖苷酶(β-N-acetylgucosaminidase,GlcNAcases)活性的影响,为深入解析家蚕GlcNAcases的生物学功能提供参考。【方法】利用微量注射器注射蜕皮激素20E和保幼激素JH,分别测定6、12、18、24和48 h家蚕幼虫血淋巴、脂肪体、中肠、表皮和丝腺中GlcNAcases的活性变化情况。【结果】在JH处理组,家蚕幼虫血淋巴GlcNAcases活性在12 h便开始显著增高,在18、24和48 h持续极显著高于对照组;在20E处理组,血淋巴GlcNAcases活性仅在24和48 h显著高于对照组。对于20E处理组和JH处理组,脂肪体组织GlcNAcases的活性变化情况相似,在6、12和18 h酶活性无显著变化,在24和48 h极显著高于对照组。经20E或JH处理后,中肠组织GlcNAcases活性在6和12 h均略高于对照组,但与对照组相比差异不显著;在18 h开始显著高于对照组,在24 h极显著高于对照组,随后在48 h酶活性降低至对照组水平。20E处理后,表皮GlcNAcases活性在12 h开始显著高于对照组,在18和24 h持续显著高于对照组,48 h酶活性降低至对照组水平。JH处理后,表皮组织GlcNAcases活性在12、18和24 h极显著低于对照组,在48 h恢复至对照组水平。丝腺组织中的GlcNAcases活性在20E处理12 h开始高于对照组,但差异不显著,随后酶活性持续增强,在18和24 h极显著高于对照组;在48 h有所降低,但仍显著高于对照组。JH处理12 h GlcNAcases活性开始降低,但与对照组相比差异不显著,18 h开始显著低于对照组,24和48 h持续极显著低于对照组。【结论】蜕皮激素20E和保幼激素JH对家蚕幼虫血淋巴、脂肪体和中肠中GlcNAcases活性具有一定的激活作用。在表皮和丝腺组织中,20E能促进并激活GlcNAcases的活性,而JH则抑制其的活性。这提示GlcNAcases在家蚕幼虫不同组织发挥的功能并不完全相同,并且不同激素对GlcNAcases活性的影响效果亦存在差异。

黏虫保幼激素结合蛋白基因MsJHBP3生物学功能及对黏虫生长发育的影响

保幼激素结合蛋白(juvenile hormone binding protein,JHBP)是一类载体蛋白,与保幼激素(juvenile hormone,JH)结合形成复合体后将保幼激素运送到靶器官处调控昆虫的生长发育。本试验在黏虫Mythimna separata转录组中获得7条保幼激素结合蛋白基因,筛选获得一条经保幼激素诱导后高表达的保幼激素结合蛋白MsJHBP3(GenBank登录号:MZ577068),c DNA全长为839bp,开放读码框长度729bp,编码242个氨基酸,氨基酸等电点为5.35,分子量为27.02kDa。不同发育阶段研究表明,Ms JHBP3在蛹期表达量最高,2龄表达量最低。RNA干扰处理4龄幼虫后6 h基因抑制效率最好,达79.72%。干扰后虫体内保幼激素含量为对照的1.14倍;羽化率和化蛹率均较对照组显著降低,羽化率下降7.42%,化蛹率下降3.75%;Ms JHBP3干扰后转录组测序数据分析共获得212个差异基因,其中105个上调基因,107个下调基因,其中保幼激素甲基转移酶基因、保幼激素环氧水解酶基因、保幼激素酯酶基因均上调。本研究表明MsJHBP3影响黏虫生长发育并参与调控JH代谢。本研究结果为黏虫生长发育关键基因的挖掘提供基础数据,为黏虫生物防治提供新的靶标基因和途径。

褐飞虱翅型分化调控机制的研究进展

昆虫翅多型作为生物可塑性发育的典型代表,是昆虫对复杂多变环境适应进化的结果。褐飞虱Nilaparvata lugens是一种典型的翅多型昆虫,若虫可发育成短翅型或长翅型成虫,后者的远距离迁飞特性造成褐飞虱在亚洲稻区大面积为害。20世纪60年代以来,前人针对褐飞虱翅多型的发生机理进行了大量研究,发现种群密度、寄主植物质量、温度和光周期等诸多环境因子以及保幼激素均能够影响翅型比例。近20年来,得益于基因组学、RNAi和基因编辑等生物技术的发展,褐飞虱翅型分化的分子机制研究取得了突破性进展,发现了褐飞虱翅型分化的开关基因FoxO,沉默或敲除FoxO会导致飞虱发育为长翅型;而胰岛素信号通路能够磷酸化FoxO抑制其进入细胞核,从而参与翅型分化调控;锌指转录因子Zfh1能够以启动子结合的方式调节FoxO的转录,与胰岛素信号通路平行调控翅型分化;另一个锌指转录因子Rotund能够与FoxO互作共同调控褐飞虱翅多型。此外,性别决定基因Transformer-2和c-Jun氨基末端激酶通路等也能够影响翅型分化,表明褐飞虱的翅型分化存在多样化的分子调控机制。鉴于半翅目不同亚目间的翅多型机制均有所不同,对褐飞虱翅型分化机制的解析远不足以阐明半翅目乃至整个昆虫纲的翅多型机制,但其研究成果能够引领未来对昆虫翅多型机制的探索研究,并加深人们对昆虫翅及组织可塑性发育与进化的理解。

GC-MS联用技术检测水性化妆品中性激素成分的方法研究

[目的 ]研究建立水性化妆品中性激素成分的测定方法。 [方法 ]采用气相色谱 质谱 (GC MS)联用技术同时分析水性化妆品中的 7种性激素成分。样品经提取、去脂、使用C18固相提取小柱净化 ,目标物用七氟丁酸酐衍生化 ,用GC MS SIM分析。 [结果 ] 7种性激素的平均回收率在 75 %～ 10 9.7%之间 ,方法检出限为 0 .0 2 5～ 0 .0 5 0 μg/ml ,方法相对标准偏差为 8.4%～ 16.3 %。 [结论

蜂巢小甲虫保幼激素环氧水解酶基因JHEH1和JHEH1-2生物信息学及表达分析

保幼激素环氧水解酶(juvenile hormone epoxide hydrolase, JHEH)是调节昆虫保幼激素(juvenile hormone, JH)代谢的关键酶之一,是选择性杀虫剂的潜在靶标。本研究利用生物信息学方法对蜂巢小甲虫JHEH1和JHEH1-2基因编码蛋白的理化特性、结构特征和系统进化进行分析,采用RT-qPCR技术检测并分析蜂巢小甲虫成虫不同发育时期卵巢(未出土,1日龄、2日龄和3日龄)和未出土成虫不同组织(卵巢、脂肪体、足、胸部、头)中JHEH1和JHEH1-2的相对表达量。结果表明,预测JHEH1编码460个氨基酸,等电点(pI)为8.06,蛋白分子式C_(2425)H_(3707)N_(603)O_(660)S_(16);JHEH1-2编码461个氨基酸,等电点(pI)为8.70,蛋白分子式C_(2420)H_(3713)N_(597)O_(656)S_(15);两者分子量均为52 kDa,均具有环氧水解酶的N端结构域。系统进化树分析表明,蜂巢小甲虫JHEH1与光肩星天牛Anpoploppor aglabripennis的JHEH聚为一支;JHEH1-2较为保守,其分支处于的置信度较低。RT-qPCR结果显示,蜂巢小甲虫JHEH1和JHEH1-2在成虫不同发育时期和各组织中均有表达,且在未出土成虫的卵巢中高表达(P<0.05),表明JHEH在卵巢发育过程中发挥重要作用。本研究可为后续深入研究JHEH基因对蜂巢小甲虫生长发育调控机制提供理论基础。

蜜蜂越冬期卵黄原蛋白和保幼激素的表达特性研究

为了探究蜜蜂越冬期体内卵黄原蛋白(Vitellogenin,Vg)和保幼激素(Juvenile hormone,JH)的表达特性。本试验分别采集夏繁期(7月)和不同越冬时期(11月、12月、1月、2月)的珲春黑蜂工蜂,通过酶联免疫吸附试验方法检测Vg、JHⅢ及超氧化物歧化酶(Superoxide Dismutase,SOD)的浓度变化,采用qRT-PCR方法检测Vg、JH代谢相关基因的表达量。结果表明:珲春黑蜂越冬期Vg浓度高于夏繁期,在不同越冬期Vg浓度总体呈现先上升后下降的趋势;Vg基因的变化趋势与Vg浓度相一致,而VgR基因表达量与SOD浓度变化趋势相一致,在越冬期水平高于夏繁期,且在整个越冬期呈现下降的趋势。珲春黑蜂越冬期JHⅢ浓度低于夏繁期,且随着越冬持续进行总体呈现持续上升的变化趋势;MFE基因的变化趋势与JHⅢ浓度相近;JHAMT基因表达量越冬期显著高于夏繁期,在整个越冬期呈现先上升后下降的趋势。本研究结果表明,蜜蜂越冬期体内存在Vg和JHⅢ间负相关的调节模型,其通过Vg、JHⅢ代谢相关基因的表达来提高越冬蜂抗氧化能力和抗寒性,为西方蜜蜂抗寒分子机制的深入研究提供了新的研究思路。