PBAN对亚洲玉米螟(Ostrinia furnacalis)性外激素生物合成路线的控制(英)

去头处理致使亚洲玉米螟性外激素的含量显著地下降到很低的水平。注射雄性或雌性玉米螟头部提取物或合成PBAN(激活外激素生物合成神经肽)可使外激素的含量得以恢复。因此可知玉米螟外激素的产生系受一种类PBAN因子控制。玉米螟性外激素生物合成路线由棕榈酸的生物合成开始,然后经14位脱饱和化,碳链缩短,还原和乙酰化形成外激素顺和反12—十四碳烯乙酸酯。为了阐明受PBAN控制的生物合成步骤,研究了不同的标记前体掺入外激素及其中间体的情况。根据结果推论,PBAN主要通过调节由乙酸酯到棕榈酸的生物合成步骤来控制外激素生物合成。     

昆虫的性外激素都是由雌虫分泌的吗?

昆虫进入性成熟期后 ,能够通过产生并且释放性外激素来引诱同种异性个体前来交尾。大多数昆虫的性外激素是由雌虫产生的 ,如常见的二化螟、棉红铃虫、梨小食心虫、舞毒蛾和马尾松毛虫等农业害虫 ,都是由雌虫产生并且释放性外激素来引诱雄虫的。虽然雌虫产生的性外激素的数量很少 ,但是对雄虫却有着强烈的引诱作用。据估计 ,1只雌虫 1次产生的性外激素的数量大约是 0 .0 0 5μg～ 1μg,但是它却能把远至数百米甚至上千米以外的雄虫引诱过来交尾。也有少数种类的昆虫 ,是由雄虫产生并且释放性外激素来引诱雌虫的 ,例如蝶类、地中海果蝇和锥蝇…     

水稻螟虫神经肽PBAN及其受体序列的生物信息学分析

【目的】性信息素合成激活肽(PBAN)是控制昆虫产生性信息素的激素,本文旨在分析水稻螟虫神经肽PBAN及其受体的序列。【方法】通过t Blastn同源检索从水稻螟虫基因组和转录组数据库中鉴定水稻螟虫PBAN神经肽及其受体序列,在此基础上进行序列比对及系统发生分析。【结果】发现二化螟Chilo suppressalis、三化螟Tryporyza incertulas和大螟Sesamia inferens的PBAN成熟肽序列均含有33个氨基酸残基,其C端五肽序列完全相同,3种水稻螟虫PBAN多肽相似度为54.55%~63.64%;发现二化螟PBAN受体3个异构体全长氨基酸序列(PBANR-A、PBANR-B和PBANR-C),均含有7个跨膜区域。【结论】进化树分析发现不同昆虫PBAN神经肽及其受体存在一定的保守性和多样性,并且在进化树上的位置几乎与昆虫系统发育分类一致,推测PBAN神经肽和PBAN受体在昆虫系统进化过程中可能存在协同进化现象。本研究为水稻螟虫PBAN神经肽及其受体的结构和功能分析提供基础。     

鱼类性外激素的研究进展

外激素(Pheromon)是指动物释放于体外的,能引起同种另一个体产生一种或多种特异性反应的化学物质。外激素在动物个体间的化学通讯中起着非常重要的作用,国内外学者对外激素的研究多集中在昆虫和哺乳动物。近年来,对鱼类性外激素(Sexpheromone)的研究受到越来越多的重视,一方面,性外激素在吸引异性。       

昆虫的外激素

外激素Pheromone这个名词,是由Karlson et Luscher于1959年首先创议采用的,它是昆虫分泌到体外的挥发性物质,是对同种昆虫的其它个体发出的化学信号,能影响它们的行为(或发育),故有人又称之为信息素。现在已经发现的昆虫外激素有性外激素、结集外激素、追踪外激素及告警外激素等等。目前应用前途较大,研究最多的是性外激素,所以本文只着重简介昆虫的性外激素。     

昆虫性外激素8-十二碳烯醋酸酯顺、反异构体的色层分离法

利用性外激素防治害虫是近年来发展起来的一种新途径。已知许多鳞翅目害虫的性外激素的分子中含有一个或几个双键而双键的几何构型对性外激素的种间特异性及生物活性影响很大。在某些昆虫的性外激素中混进一些相反的异构体,在在会降低甚至完全丧失生物活性;而在另外一些昆虫性外激素中,必须加入适量的相反导构体才能获得最高的诱蛾活性。因此,在昆虫性外激素的合成与应用的研究中,顺、反异构体的鉴定和分离是一个十分重要的问题。     

PBAN/pyrokinin神经肽类及其基因的研究进展

昆虫在其生长发育过程中,如胚胎发育、蜕皮变态、滞育、迁飞、代谢、生殖等都离不开神经肽的调控。信息素合成激活肽(pheromone biosynthesis activating neuropeptide,PBAN)和Pyrokinin神经肽是C端具有五肽FXPRL(X=S,V,T,G等)(苯丙-X-脯-精-亮氨酸)序列的一类神经肽,在昆虫的生长发育中起重要的生理功能,如性信息素的合成、控制表皮色素、促进胚胎滞育和刺激内脏肌肉收缩等重要的生理功能。因此近几年对PBAN/pyrokinin神经肽的鉴定、加工、作用和降解方式的研究成为研究的热点,为研制高效、低毒、专一性强、无公害的杀虫剂提供了思路。介绍了PBAN/pyrokinin神经肽类及其基因的研究进展,并对PBAN/pyrokinin神经肽在害虫防治中的应用进行了展望。     

玉米螟性外激素腺体组织学研究

昆虫性外激素的研究,近年来有了迅速发展。关于性外激素腺体的研究,国外已有很多报道,我国目前尚未见有报道。Klun(1968)报道欧洲玉米螟(Ostriniamubilalis)性外激素腺体在雌蛾腹部最后两节的节间膜上。1975年以来,我们对本地玉米螟(Ostrinia furna-calis~*)性外激素进行了分离工作,进而对玉米螟发育时期的性外激素腺体组织学作了研究。     

昆虫性外激素嗅觉过程的神经生物学研究

本文从外周、中枢和行为三个不同层次,探讨昆虫对性外激素感受的嗅觉过程。通过对大量昆虫的性外激素组分化学结构鉴定,以及结构一活性关系的研究,促进了对嗅觉机制的了解。对于嗅觉中枢过程的了解是很初步的,有待进一步深入研究。     

铃夜蛾属昆虫性信息素生物合成及内分泌调控

综述了铃夜蛾属Helicoverpa昆虫性信息素生物合成途径及内分泌因子的调控作用 ,包括信息素生物合成激活神经肽 (PBAN)和信息素生物合成抑制肽 (PSP)等的来源、结构和作用机制及一些种中保幼激素 (JH)和章鱼胺 (OA)对性信息素生物合成的作用 ,并展望了未来的研究方向。     

Factors affecting pheromone production in beetles

Pheromone production and/or release by beetles is coordinated with a variety of behavioral, physiological, and environmental factors. To data, two basic mechanisms for the regulation of pheromone biosynthesis in beetles have been proposed. Pheromone biosynthesis may simply be dependent on the availability of biosynthetic precursors. Alternatively, certain stimuli or events may trigger pheromone biosynthesis via juvenile hormone (JH) action. JH may either act directly at the site of pheromone biosynthesis to enhance pheromone production or may act indirectly, through a brain hormone (which might be related to the pheromone biosynthesis activating neuropeptide) or through effects on antennal sensory response. Knowledge of the regulation of the initiation and termination of pheromone biosynthesis is reviewed. Mechanisms by which pheromone stereochemistry is controlled are also discussed. This is an important aspect of pheromone production in Coleoptera, since slight changes in the stereochemistry can completely alter the activity of the molecule. © 1994 Wiley-Liss, Inc.     

Mating Effect on Sex Pheromone Production of the Oriental tobacco budworm,Helicoverpa assulta

This study was undertaken to clarify the suppression phenomenon of sex pheromone production after mating and its relationship to the physiological mechanism in adult females of Helicoverpa assulta, and determine the mating factor from males causing depletion of sex pheromonc production. Sex pheromone production of H. assulta females was mostly terminated in 3 hours after mating. Mated females maintained with a low titer of sex pheromone until 3 days when it started to increase again, which showed a characteristic of species mating more than once. The mated female again produced pheromone upon injection of pheromone biosynthesis activating neuropeptide (PBAN) or extracts of brain-suboesophageal ganglion complexes (Br-Sg) of mated female, which were shown similar pheromonotropic activities as compared with virgin females. These results indicated that the mating did not inhibit the receptivity of pheromone gland itself and PBAN biosynthesis in suboesophageal ganglion of the mated females. And it seems to support that the depletion of sex pheromone production is responsible for blocking of PBAN release from head. To investigate the mating factor from adult males, when extracts of reproductive organs of male were injected into hemocoel of virgin females evoking depletion of sex pheromone production as shown in mated female. The results suggest that a chemical substance(s) from the male reproductive organs could be responsible for the loss of sex pheromone biosynthesis in H. assulta.     

Regulation of pheromone production by female pink bollworm moths Pectinophora gossypiella (Sanders) (Lepidoptera: Gelechiidae)

Abstract. We present in this study data which indicate that there is a diel periodicity in the pheromone production of the pink bollworm moth Pectinophora gossypiella (Sanders) (Lepidoptera: Gelechiidae) but that it is not well defined. Moreover the control mechanism of pheromone production differs somewhat from that reported for other moths. No pheromonotropic response was obtained when photophase females were injected with synthetic Helicoverpa zea pheromone biosynthesis activating neuropeptide (Hez-PBAN). After decapitation for 24 h, Hez-PBAN did not induce pheromonotropic activity above control levels, which themselves remained relatively high. No effect on pheromone production was observed after treatment with the non-steroidal ecdysone agonist (RH5999). Decapitation for 72 h resulted in a significant drop in the control levels of pheromone titres. After decapitation for 72 h, stimulation by injections of Hez-PBAN and pink bollworm head extracts was observed. In addition, an enhancement of the PBAN stimulation was observed when combined with severance of the ventral nerve cord before injection. On the other hand, pink bollworm head extracts did not cross-react with Hez-PBAN antiserum in a radioimmunoassay, indicating that the pheromonotropic factor present is sufficiently different from Hez-PBAN and does not recognize the antigenic binding sites. In studies using isolated abdomen and pheromone gland cultures in vitro , no stimulation of de novo pheromone biosynthesis was observed but a 3-fold increase in the de novo fatty acid biosynthesis was detected in pheromone gland cultures.     

Ant Trail Pheromone Biosynthesis Is Triggered by a Neuropeptide Hormone

Our understanding of insect chemical communication including pheromone identification, synthesis, and their role in behavior has advanced tremendously over the last half-century. However, endocrine regulation of pheromone biosynthesis has progressed slowly due to the complexity of direct and/or indirect hormonal activation of the biosynthetic cascades resulting in insect pheromones. Over 20 years ago, a neurohormone, pheromone biosynthesis activating neuropeptide (PBAN) was identified that stimulated sex pheromone biosynthesis in a lepidopteran moth. Since then, the physiological role, target site, and signal transduction of PBAN has become well understood for sex pheromone biosynthesis in moths. Despite that PBAN-like peptides (∼200) have been identified from various insect Orders, their role in pheromone regulation had not expanded to the other insect groups except for Lepidoptera. Here, we report that trail pheromone biosynthesis in the Dufour''s gland (DG) of the fire ant, Solenopsis invicta, is regulated by PBAN. RNAi knock down of PBAN gene (in subesophageal ganglia) or PBAN receptor gene (in DG) expression inhibited trail pheromone biosynthesis. Reduced trail pheromone was documented analytically and through a behavioral bioassay. Extension of PBAN''s role in pheromone biosynthesis to a new target insect, mode of action, and behavioral function will renew research efforts on the involvement of PBAN in pheromone biosynthesis in Insecta.     

Drosophila melanogaster sex peptide stimulates juvenile hormone synthesis and depresses sex pheromone production in Helicoverpa armigera

Previous studies demonstrate that virgin female adult Helicoverpa armigera (Lepidoptera: Noctuidae) moths exhibit calling behaviour and produce sex pheromone in scotophase from the day after emergence, and that mating turns off both of these pre-mating activities. In the fruit fly Drosophila melanogaster, a product of the male accessory glands, termed sex peptide (SP), has been identified as being responsible for suppressing female receptivity after transfer to the female genital tract during mating. Juvenile hormone (JH) production is activated in the D. melanogaster corpus allatum (CA) by SP in vitro. We herein demonstrate cross-reactivity of D. melanogaster SP in the H. armigera moth: JH production in photophase virgin female moth CA in vitro is directly activated in a dose-dependent manner by synthetic D. melanogaster SP, and concurrently inhibits pheromone biosynthesis activating neuropeptide (PBAN)-activated pheromone production by isolated pheromone glands of virgin females. Control peptides (locust adipokinetic hormone, AKH-I, and human corticotropin, ACTH) do not inhibit in vitro pheromone biosynthesis. Moreover, SP injected into virgin H. armigera females, decapitated 24 h after eclosion, or into scotophase virgin females, suppresses pheromone production. In the light of these results, we hypothesize the presumptive existence of a SP-like factor among the peptides transmitted to female H. armigera during copulation, inducing an increased level of JH production and depressing the levels of pheromone produced thereafter.     

CONTROL OF SEX PHEROMONE BIOSYNTHETIC PATHWAY BY PBAN IN ASIAN CORN BORER OSTRINIA FURNACALlS*

Abstract Sex pheromone titer in Ostrinia furnacalis was significantly decreased to a very low level by decapitation, but it could be restored by injection of head extract prepared from both male and female moths or synthetic pheromone biosynthesis activating neuropepide (PBAN). This fact indicates that pheromone production is under the control of a PBAN-like factor. The sex pheromone biosynthetic pathway of O. furnacalis originates with the biosynthesis of palmitic acid and followed by A14 desaturation, chain shortening, reduction and acetylation to form the pheromone components, (Z) and (E)-12-tetradecenyl acetate. In order to determine which step in the pathway is controlled by PBAN, the incorporation of different labeled precursors into the pheromone and its intermediate were studied. Our results suggest that PBAN controls pheromone biosynthesis in O. furnacalis by mainly regulating an early step from acetate to palmitic acid.     

Neuroendocrine control of pheromone production in moths

In many moth species regulation of pheromone production has been attributed to the timely release of a pheromone biosynthesis activating neuropeptide (PBAN). The gene encoding PBAN has been sequenced in two moth species. Immunochemical studies as well asin situ hybridization and Northern analysis of PBAN encoding mRNA have localized the neuroendocrine cells responsible for the production of PBAN and have traced the neuronal network of PBAN immunoreactivity. Release into the bloodstream has been demonstrated, the target tissue delineated, and the signal transduction pathway and its modulation analyzed. This paper reviews the current status of research concerning the neuroendocrine control of pheromone production in Lepidopterans and presents some recent developments concerning the receptors involved in the pheromonotropic activity. In this study, we report on the use of a biologically active photoaffinity-biotin-labeled derivative of PBAN N-[N-(4-azido-tetrafluorobenzoyl-biocytinyloxyl-succinimide) and show the presence of a protein (estimated molecular weight of 50 kDa) which specifically binds to PBAN in membrane preparations of pheromone glands. Contribution from the Agricultural Research Organization, The Volcani Center, Bet Dagan, Israel. No.2279-E, 1997 series