Immunolocalization of general odorant-binding protein in antennal sensilla of moth caterpillars

Antennae of Bombyx mori and Helicoverpa armigera larvae were immunolabelled with antisera raised against the pheromone-binding protein or the general odorant-binding protein 2 of Antheraea polyphemus to assign the expression of these proteins to individual sensilla and to compare the localization pattern with that in sensilla of adult moths. Specific labelling of antennal sensilla was only obtained with the antiserum against general odorant-binding protein 2. Among the few sensilla present on the antenna the three large sensilla basiconica, which are suspected to be olfactory in function, were labelled. These sensilla are compound sensilla consisting of several sensillum units which form a common sensory hair. The hair is single-walled and pierced by many pores. Labelling of sensillum compartments was the same as in sensilla of adults. Prominent labelling of the sensillum lymph is accompanied by labelling of secretory organelles in the two outermost auxiliary cells and of endocytotic pathways in all sensillum cells. The results suggest that general odorant-binding protein is expressed in single-walled multiporous sensilla of presumed olfactory function on the antenna of moth larvae. The overall identity of the localization pattern for general odorant-binding protein between larval and adult sensilla implies a similar role of these proteins in olfactory stimulus transduction.     

Expression of chemosensory proteins in hairs on wings of Locusta migratoria (Orthoptera: Acrididae)

The hairs on the wings of Locusta migratoria were observed and mapped using light microscopy, as well as by scanning and transmission electron microscopy. Based on their ultrastructure, we can distinguish four main types of hairs on the wings of adult L. migratoria , viz, short, medium and long hairs, and sensilla chaetica. The long hairs are located only on the ventral surface of the hindwing, whereas the other three types are present both on the dorsal and ventral surfaces of forewing and hindwing in both sexes. Medium hairs and sensilla chaetica are significantly more abundant on the dorsal surface of forewings in both females and males, than on the ventral surface, whereas the opposite was observed for short hairs (P < 0.01). No significant difference between males and females was observed in the density of any type of hairs (P > 0.1). Several dendritic branches, enveloped by a dendrite sheath, are situated in the lymph cavity of sensilla chaetica. Instead, no dendritic structure was observed in the cavity of the other three types of hairs. Immunocytochemical localization of chemosensory proteins (CSPs) was performed on ultrathin sections of hairs on wings. The antiserum against chemosensory proteins from L. migratoria (LmigCSP-II) strongly labelled sensilla chaetica, with gold granules only found in the outer sensillum lymph. In addition, the epidermal cell membrane of the wing was stained by the antiserum against LmigCSP-II. The other three types of hairs were never labelled. The results indicate that the wings might involve in contact chemoreception process.     

Developmental expression of odorant‐binding proteins and chemosensory proteins in the embryos of Locusta migratoria

We have investigated the development of chemosensilla and the secretion of odorant‐binding proteins (OBPs) and chemosensory proteins (CSPs) in the embryo of Locusta migratoria manilensis. We first report the changes of each sensillum in embryo just preceding hatch in detail and show that different sensilla have different developmental processes. Trichogen cells are first involved in forming the structure of pegs, and then, after retraction, they start secreting OBPs and CSPs in the sensillar lymph. The synthesis of LmigOBP1 starts during the embryogenesis about 0.5 h preceding hatching, specifically in sensilla trichodea and basiconica of the antenna. LmigOBP2, instead, was only found in the outer sensillum lymph (oSl) of sensilla chaetica of the antenna, while we could not detect LmigOBP3 in any type of sensilla of the antenna. The ontogenesis of CSPs in the embryos is similar to that of OBPs. Expression of CSPI homolog in Locusta migratoria is detected using the antiserum raised against SgreCSPI. CSPI is specifically expressed in the outer sensillum lymph of sensilla chaetica of the antenna, and anti‐LmigCSPII dose not label any sensilla of the embryos. These data indicate that in locusts, OBPs and CSPs follow different temporal expression patterns, and also that OBPs are expressed in different types of sensilla. © 2009 Wiley Periodicals, Inc.     

山茱萸蛀果蛾幼虫触角和口器感器的超微形态

【目的】探索寄主范围不同的蛀果蛾科(Carposinidae)幼虫感器之间是否存在差异。【方法】采用扫描电子显微镜观察了为害山茱萸Cornus officinalis Sieb. et Zucc.的单食性蛀果害虫--山茱萸蛀果蛾Carposina coreana Kim老熟幼虫触角和口器感器的超微形态。【结果】山茱萸蛀果蛾幼虫触角柄节未见感器分布, 梗节上有2个刺形感器和3个锥形感器, 鞭节上有1个栓锥感器和3个锥形感器。口器上共有6种感器： 刺形感器数量多, 分布广; 栓锥感器主要分布在颚叶、 下颚须和下唇须上; 指形感器位于内唇和下颚须端节侧缘; 锥形感器和板形感器仅存在于下颚上; 内唇感器为内唇所特有。【结论】蛀果蛾幼虫触角和口器的感器与寄主范围之间未发现严格的对应关系。     

The chemosensilla on tarsi of Locusta migratoria (Orthoptera: Acrididae): Distribution,ultrastructure, expression of chemosensory proteins

The chemosensilla on the tarsi of Locusta migratoria were mapped using light microscopy, as well as scanning and transmission electron microscopy. Only chemosensilla chaetica were found on the tarsi. On the basis of their ultrastructure, these can be grouped into three main subtypes: short, long, and sunken sensilla chaetica. Short sensilla chaetica can be further divided into two groups containing 6 or 7 neurons. Long sensilla chaetica are mainly located on the lateral surface of the tarsi. Short sensilla chaetica were mainly found on the dorsal surface of the tarsi. Sunken sensilla chaetica were only found on the ventral surface, such as the pulvilli and arolium. Immunocytochemical localization of chemosensory protein (CSP) was performed on ultrathin sections of chemosensilla on tarsi. The antiserum against LmigCSP‐II intensively labeled all three types of sensilla chaetica. Gold granules were concentrated in the outer sensillum lymph surrounding the dendrite sheath, while the inner sensillum lymph containing dendrite branches was never labeled. Massive labeling with the anti‐LmigCSP‐II was also found in cuticle of the pulvilli on the ventral surface of tarsi. J. Morphol. 2009. © 2009 Wiley‐Liss, Inc.     

Immunolocalization of pheromone-binding protein and general odorant-binding protein in olfactory sensilla of the silk moths Antheraea and Bombyx

The distribution of odorant-binding proteins among olfactory sensilla of three moth species was studied by immuno-electron microscopy. Two polyclonal antisera were used in a post-embedding labelling protocol on sections of cryo-substituted antennae. The first was directed against the pheromone-binding protein (PBP) of Antheraea polyphemus, the second against the general odorant-binding protein (GOBP) of the same species. Immunoblots showed that these antisera were highly specific; both antisera did, however, cross-react with related proteins in the related species A. pernyi, and in the bombycid moth B. mori. PBP and GOBP were localized only in olfactory sensilla trichodea and sensilla basiconica, the principal site being the sensillum lymph surrounding the sensory dendrites. In the males of all three species, the pheromone-sensitive long sensilla trichodea exclusively contained PBP. the majority of the sensilla basiconica in both sexes in these species contained GOBP; these sensilla are known to respond to plant and other general odours. Some sensilla were not labelled by either antiserum; presumably, these held an odorantbinding protein of a different subfamily. Never were PBP and GOBP co-localized in the same sensillum. Two observations deserve special attention: (1) PBP was also found in a few sensilla in females, and (2) in B. mori, where the long sensilla trichodea have a different functional specificity in males (pheromone) and females (plant odours), the expression of the odorant-binding protein (males: PBP; females: GOBP) is similarly different. The distinct and complex distribution pattern of odorant-binding proteins supports the notion that these proteins participate in stimulus recognition.Dedicated to Professor Ya.A. Vinnikov on the occasion of his 85. birthdayThis work was partly supported by DFG grant ste 501/3-1.     

梨小食心虫幼虫感受器扫描电镜观察

梨小食心虫Grapholita molesta(Busck)是一种世界性蛀果害虫,主要以幼虫钻蛀蔷薇科果树的嫩梢和果实进行为害.本文利用扫描电子显微镜观察了梨小食心虫幼虫的超微形态和感受器.结果表明,幼虫触角上有3种类型的感受器:2个刺形感受器、6个锥形感受器和1个栓锥形感受器.上唇有6对刺形感受器.上颚的前端有切齿叶.在下颚的轴节和茎节各有1个刺形感受器.每个外颚叶有3个短而尖的锥形感受器、2个大的栓锥形感受器和3个刺形感受器.体节末梢的下颚须有7个锥形感受器、1个栓锥形感受器.下颚须的末端有1个指形感受器和2个板形感受器.每个下唇须末端具有1个尖锥状刺形感受器和1个长的栓锥形感受器.胸足与腹足上也分布有不规则的毛型感受器和刺型感受器.该研究将为进一步阐明梨小食心虫与其寄主的关系提供形态学的理论基础.     

Morphology of antennal,maxillary palp and labial palp sensilla in different larval instars of the Asian long‐horned beetle,Anoplophora glabripennis (Motschulsky) (Coleoptera: Cerambycidae)

The Asian long‐horned beetle (ALB) is one of the most important international trunk‐boring insect pests of forest trees, which has caused enormous losses in the forests of China, the USA and some countries in Europe. To investigate the morphology of the antennal, maxillary palp and labial palp sensilla in the five larval instars of the ALB, scanning electron microscopy was used to determine the typology, morphology, number and distribution of the sensilla. The antennae had two types of sensilla: the sensilla twig basiconica (s.t.b.) and sensilla basiconica. Three different types of sensilla were observed on the maxillary palps, which were the sensilla digitiformia, the sensilla chaetica and the s.t.b. The labial palps had two types of sensilla: the sensilla chaetica and the s.t.b. The s.t.b. had seven total subtypes, and the sensilla basiconica had two subtypes. The typology, quantity and distribution of sensilla on the antennae, maxillary palps and labial palps remained constant in the five larval instars, but the dimensions of all sensilla types increased throughout the development. We discussed the mechanoreception and the chemoreception of ALB larvae inside the host tree to provide a theoretical understanding and information for further research on the behaviour and the electrophysiology of this devastating forest pest.     

灰茶尺蠖成虫触角及幼虫头部感器超微结构

【目的】明确灰茶尺蠖Ectropis grisescens成虫触角及幼虫头部感器的种类、形态、数量和分布,以探讨灰茶尺蠖的行为机制。【方法】利用扫描电镜技术观察灰茶尺蠖雌、雄成虫触角和5龄幼虫头部感器的超微结构。【结果】灰茶尺蠖成虫触角上分布有8种感器,分别是栓锥形感器、耳形感器、毛形感器(Ⅰ-Ⅳ)、B?hm氏鬃毛、腔锥形感器(Ⅰ和Ⅱ)、鳞形感器、锥形感器(Ⅰ和Ⅱ)和刺形感器。其中,栓锥形感器仅分布在雌蛾触角上,耳形感器、毛形感器(STⅠ-Ⅲ)仅分布在雄虫触角上。5龄幼虫触角上着生1个栓锥形感器、1个锥形感器和2个刺形感器;上唇着生有6对刺形感器,内唇着生有3对刺形感器和1对指形感器;上颚基部外侧着生有2个刺形感器;下颚及下颚须着生有5个刺形感器、9个锥形感器和2个栓锥形感器;下唇须着生有1个锥形感器和1个刺形感器;吐丝器前端着生有1对刺形感器。【结论】灰茶尺蠖雌、雄成虫触角感器存在性二型性,且雄虫上感器种类和数量较多,据此推测雄虫感受寄主植物或性信息素的能力较强;幼虫头部感器具有嗅觉和味觉功能,在其判断食物的种类和适应性等生态行为中发挥重要作用。     

Ultrastructure of sensilla on the maxillary and labial palps of three species (Coleoptera: Staphylinidae: Staphylininae)

Most species of Staphylinidae are predators in an agroecosystem. They acquire prey information from their environment through receptors. In this study, the sensilla on maxillary and labial palps of Philonthus kailiensis, Philonthus lewisius and Quedius robustus were examined with scanning electron microscopy to identify and analyse the external morphology and distribution of the sensilla to enhance our knowledge of the sensilla of Staphylinidae and provide a rationale of taxonomical studies on the two genus. Results showed that the sensilla are classified into six types: Böhm bristles, sensilla chaetica, sensilla furcate, sensilla coeloconica, sensilla placodea and sensilla basiconica. No sexual dimorphism exists among the three species. The relationships and functions of sensilla on maxillary and labial palps were also speculated. There may be a certain correlation between the sensilla on maxillary and labial palps of the staphylinid and its habitat.     

西藏飞蝗触角感器的扫描电镜观察

应用扫描电镜对西藏飞蝗Locusta migratoria tibetensis Chen触角的外部形态结构及其感器进行了观察和研究.结果表明,西藏飞蝗触角上存在5种感器即毛形感器、刺形感器、腔锥形感器、锥形感器和腔形感器.通过对各种感器的形态特点进行描述,发现西藏飞蝗群居型与散居型、蝗蝻与成虫、雌性与雄性的感器在类型...     

Ultrastructure and distribution of sensilla on the maxillary and labial palps of Chlorophorus caragana (Coleoptera: Cerambycidae)

Chlorophorus caragana is a species of long‐horned beetle that damages Caragana davazamcii Sancz. (Fabales: Papilionaceae) bushes in desert areas in China. The beetles cause substantial damage to local forestry plantations and the environment. Sensilla on the maxillary and labial palps of coleopterans a allow the insects to recognize their host plants. We used scanning and transmission electron microscopy to study the ultrastructure, distribution, and abundance of various sensilla on the maxillary and labial palps of C. caragana. We found four types of sensilla including ten subtypes: one of Böhm's bristles, three of sensilla chaetica, one of digitiform sensilla, and five of sensilla twig basiconica. The types and distribution of the sensilla on the maxillary and labial palps were highly similar between males and females. Finally, this article discusses the functions of the sensilla of related species in recognizing hosts and the significance of gustation studies in the context of the control of C. caragana.     

甜菜夜蛾幼虫触角及口器上感器形态描述(鳞翅目,夜蛾科)

甜菜夜是一种危害严重的世界性农业害虫,其幼虫识别寄主取食的机理及转主危害取决于其嗅觉感器的识别机理。本文运用扫描电镜对甜菜夜蛾幼虫头部触角及口器感器形态进行了观察,描述了感器的种类、数量和分布,并结合文献资料对其功能进行了探讨,试图解析昆虫的取食机制。     

锈翅蚁蛉头部附器感器的扫描电镜观察

利用扫描电镜对锈翅蚁蛉Myrmeleon ferrugineipennis Bao&Wang雌雄成虫头部触角及口器感器的形态进行观察,描述了感器的种类、数量和分布,以期解析其取食机制。结果表明:锈翅蚁蛉触角上存在10种感器,即毛形感器、锥形感器、刺形感器、腔形感器、钟状感器、鳃形感器、耳形感器、盘形感器、舌形感器和Bhm氏鬃毛,其中毛形感器有3种亚型,数量最多;耳形感器、腔形感器和钟状感器仅在雌成虫触角上发现,而舌形感器和鳃形感器仅在雄成虫触角上发现;在锈翅蚁蛉触角鞭节近末端扁平匙状处各有1枚盘形感器,其形状和位置在雌雄虫上有差异。鳃形感器和盘形感器在已有的昆虫感器研究中未见报道,是新发现的昆虫触角感器。下颚须、下唇须上均发现锥形感器,下唇须上的数量多于下颚须;此外,下颚须上还存在钟状感器。     

Morphology and distribution of sensilia on the cephalic appendages,tarsi and ovipositor of the European sunflower moth,Homoeosoma nebulella Den. & Schiff. (Lepidoptera : Pyralidae)

Sensilla on male and female antennae, mouthparts, tarsi and on the ovipositor of the European sunflower moth, Homoeosoma nebulella (Lepidoptera : Pyralidae) have been investigated by means of scanning electron microscope. The antennal flagellum bears multiporous sensilla (trichodea, basiconica, auricillica, coeloconica) and uniporous sensilla (chaetica, styloconica). A sexual dimorphism is found in the numbers of sensilla trichodea (8300 in males and 6000 in females) and sensilla basiconica (1150 in females and 650 in males). The proboscis has uniporous s. styloconica, multiporous s. basiconica (described for the first time in Lepidoptera), aporous s. chaetica, and some rare uniporous s. basiconica in the food channel. The labial palp-pit organ houses multiporous s. coeloconica, while the maxillary palps have aporous sensilla. Tarsi of both sexes possess one type of aporous s. chaetica and 2 types of uniporous s. chaetica. There is no significant difference in the distribution of tarsal sensilla between males and females. The surface of each lobe of the ovipositor is covered by 3 types of aporous s. trichodea of different lengths and about 60 multiporous s. basiconica, sensilla unusual on the ovipositor of Lepidoptera. The role of sensilla in the oviposition site selection is discussed.     

Sensilla on the larval antennae and mouthparts of the european sunflower moth,Homoeosoma nebulella Den. and Schiff. (Lepidoptera : Pyralidae)

Sensilla on the larval antennae and mouthparts of Homoeosoma nebulella (Lepidoptera : Pyralidae) were examined with a scanning electron microscope. The antenna possesses 2 aporous sensilla chaetica, one aporous sensillum styloconicum, 3 large multiporous sensilla basiconica, and 3 small multiporous s. basiconica. The labrum bears 12 aporous s. chaetica and the epipharynx has 6 aporous flattened s. chaetica and 4 epipharyngeal sensilla. It is the first time that more than 2 epipharyngeal sensilla have been reported in caterpillars. The mandible possesses 4 aporous s. chaetica. Each galea bears 2 uniporous s. styloconica, 2 small aporous s. basiconica, one s. campaniformium and 3 aporous s. chaetica. Each maxillary palp bears a distal group of 8 uniporous s. basiconica, one large s. digitiformium and one pore plate. Minute grooves exist on the s. digitiformium. Each labial palp possesses one aporous s. chaeticum and one aporous s. styloconicum. An attempt has been made to identify the function of sensilla by comparing them with those of other larvae.     

Fine structure and distribution of antennal sensilla of the desert locust, Schistocerca gregaria (Orthoptera: Acrididae)

The fine structure and distribution of various types of antennal sensilla in three nymphal stages and in adults of both solitary-reared (solitary) and crowd-reared (gregarious) phases of the desert locust, Schistocerca gregaria, were investigated by scanning and transmission electron microscopy. Four types of sensilla were identified: sensilla basiconica, s. trichodea, s. coeloconica and s. chaetica. S. basiconica contain up to 50 sensory neurons, each of which displays massive dendritic branching. The sensillar wall is penetrated by a large number of pores. In contrast, s. trichodea contain one to three sensory neurons that branch to give five or six dendrites in the sensillar lumen; the sensillum wall is penetrated by relatively few pores. The s. coeloconica are situated in spherical cuticular pits on the antennal surface. The s. coeloconica are of two types: one type contains one to three sensory neurons with double sensillar walls penetrated by slit-like pores, whereas the second type contains four sensory neurons with non-porous double sensillar walls. The s. chaetica have a flexible socket and a thick non-porous sensillum wall and contain four sensory neurons that send unbranched dendrites to a terminal pore. A fifth sensory neuron of the s. chaetica terminates in a tubular body at the base of the hair. S. basiconica and coeloconica are normally distributed over the entire antennal flagellum, with a concentration in the middle segments; s. trichodea have three areas of concentration on the 5th, 10th and 14th flagellar segments. Sensilla chaetica are most abundant on the terminal segment. Locusts raised in solitary conditions have more olfactory sensilla (s. basiconica and s. coeloconica) than crowd-reared locusts. The difference in sensillar numbers is more evident in adults than in nymphs. These results suggest that differences in the odour-mediated behaviour of nymphs and adults, and between the phases of S. gregaria, may be attributable to differences at the sensory input level.     

小菜蛾成虫下唇须感器的超微结构及其神经元中枢投射

【目的】明确小菜蛾Plutella xylostella成虫下唇须感器的形态结构及感器神经元的投射。【方法】利用光学显微镜观察和扫描电子显微镜观察下唇须结构和感器类型,利用神经回填技术和激光共聚焦显微镜观察下唇须感器神经元在脑部的投射。【结果】小菜蛾成虫下唇须共3节,其上存在Böhm氏鬃毛、钟形感器、鳞形感器、锥形感器、微毛形感器5种不同类型的感器和一个陷窝器结构。Böhm氏鬃毛短小尖细,钟形感器形如顶部凹陷的圆帽,两种感器均分布于下唇须第1节,且大小上均无雌雄二型差异;鳞形感器形同柳叶,锥形感器粗而直,均散生于下唇须的第2和3节,两种感器在大小上均存在雌雄二型差异,其中雌性的鳞形感器显著大于雄性的,根据其雌雄二型差异现象推测雌蛾的鳞形感器可能与感受寄主植物挥发物有关;下唇须第3节中上部具有一个圆形陷窝器结构,雄虫的陷窝器内径为5.68±0.33μm,雌虫的为6.03±0.23μm,雌雄间无显著性差异;凹坑内长有表面光滑的微毛形感器。小菜蛾下唇须感器神经元主要投射于脑部咽下神经节、每个触角叶的下唇须陷窝器神经纤维球和腹神经索3条通路。【结论】阐明了小菜蛾下唇须感器的类型、分布和形态特征及其感器神经元在脑部的投射形态,为深入了解小菜蛾下唇须感器的生理和功能奠定了基础。     

Molecular cloning and bacterial expression of pheromone binding protein in the antennae of Helicoverpa armigera (Hübner)

A cDNA clone coding for pheromone binding protein was isolated from the antennae of Helicoverpa armigera by RT-PCR and (5'/3')-RACE technique. The full-length of H. armigera pheromone binding protein (HarmPBP) was 952 bp, possessing 162 amino acid residues including a signal peptide of 20 amino acids. Its predicted molecular weight and isoelectric point were 18.26 kDa and 5.23, respectively. This deduced amino acid sequence shared some common structural features with odorant-binding proteins from several moth species, including the six conserved cysteine motif, a typical characteristic of insect's odorant-binding proteins. Northern blot showed that HarmPBP is specifically expressed in the antennae of Helicoverpa armigera and more abundantly expressed in male than female. During the antennal development, HarmPBP is first expressed about 4 days prior to adult eclosion and rises to a plateau 2 days prior to adult eclosion. In order to obtain sufficient PBP for further determining its biochemical and physiological properties, a bacterical expression vector of PBP was constructed and successfully expressed in Escherichia coli. The recombinant PBP was shown to cross-react with an anti-PBP antiserum from Antheraea polyphemus. Polyclonal antibodies against HarmPBP were used to mark the distribution of the protein in olfactory sensilla. Very strong labeling was observed in the sensillum lymph of the hair lumen and of the sensillum-lymph cavity. In the male, HarmPBP is expressed in sensilla trichodea and not in sensilla basiconica, while in the female, it is expressed both in sensilla basiconica and sensilla trichodea.     

The antennae of neopseustid moths: Morphology and phylogenetic implications, with special reference to the sensilla (Insecta, Lepidoptera, Neopseustidae)

The antennae of Lepidoptera Neopseustidae were examined with the scanning electron microscope. The studied species, Nematocentropus cfr. omeiensis, Neopseustis meyricki, Synempora andesae, Apoplania valdiviana and Apoplania penai possess nine types of antennal flagellum sensilla: multiporous large sensilla basiconica, multiporous thin sensilla basiconica, multiporous small sensilla basiconica, multiporous sensilla trichodea, multiporous sensilla coeloconica; uniporous sensilla chaetica; aporous sensilla chaetica, aporous stylus-shaped sensilla chaetica, aporous sensilla styloconica.The multiporous sensillum type here termed “multiporous large sensillum basiconicum” is unknown from other Lepidoptera and probably constitutes an autapomorphy of the family Neopseustidae. This sensillum type is remarkable by having a single base in female Apoplania and Synempora while in male Apoplania it has a bifid or trifid base, and in male Synempora it is composed of two or three incompletely separated hairs. This may be the first recorded example of a sexually dimorphic lepidopteran sensillum type. The stylus-shaped sensillum chaeticum is a primitive type which occurs only in some lower Lepidoptera.