The transparent accessory reproductive gland secretes a polypeptide into the hemolymph of male Rhodnius prolixus

The transparent accessory reproductive gland of Rhodnius prolixus synthesizes and accumulates a variety of polypeptides. Ouchterlony immunodiffusion demonstrates that the hemolymph contains proteins which react with polyclonal antibodies against extracts of transparent accessory glands. Accessory glands and hemolymph contain a 170 kDa polypeptide with similar mobility on SDS-polyacrylamide gel electrophoresis. This polypeptide reacts with antibodies against extracts of accessory glands. Surgical removal of the accessory glands prevents the appearance of the 170 kDa polypeptide in the hemolymph. In vivo labeling of accessory gland proteins with a mixture of [¹⁴C]amino acids demonstrates that the newly synthesized TARG polypeptide appears in the hemolymph between days 2 and 3 after feeding. It is concluded that a specific polypeptide which is synthesized in the transparent accessory gland is exported to the hemolymph.     

Partial characterization and isolation of earwig `allatostatins'': biological activities in earwigs and cockroaches

Allatostatins are a family of neuropeptides first isolated from the cockroach, Diploptera punctata, that inhibit juvenile hormone production in that species (but do not do so in earwigs), and inhibit hindgut muscle contractions in some insects, including the earwig, Euborellia annulipes. We examined whether material from earwig brains is similar to cockroach allatostatins biochemically, immunologically and physiologically. Brain extracts from adult female earwigs were separated by high performance liquid chromatography (HPLC), followed by radioimmunoassay using antibodies to cockroach allatostatin (Dip-AST). Fractions that co-eluted with cockroach allatostatins were immunoreactive, and at least two peaks of immunoreactivity were detected. Material from each peak at 10 nM Dip-AST equivalents inhibited juvenile hormone biosynthesis in vitro by corpora allata of 2-day virgin D. punctata cockroaches; 1 nM was less effective, and non-immunoreactive fractions failed to inhibit juvenile hormone biosynthesis. Both crude and Sep-Pak (Waters) purified extracts of brains of earwigs containing 1 nM Dip-AST equivalents failed to suppress hindgut contractions in vitro of 2-day earwigs and of brooding female earwigs. In contrast, 1 nM cockroach allostatin 1 (Dip-AST 7) reversibly inhibited hindgut contractions in vitro. These results suggested the presence of another brain factor, such as proctolin, that counteracts the inhibitory effects of Dip-AST. In support of this hypothesis, proctolin stimulated hindgut contractions in vitro at 1 nM; the effects of equal concentrations of allatostatin and proctolin varied with the stage of the female. Furthermore, HPLC-separated fractions that co-eluted with cockroach allatostatin and were immunoreactive with antibodies to Dip-AST suppressed hindgut contractions in vitro of 2-day female earwigs. Finally, crude brain extracts of earwigs suppressed earwig juvenile hormone biosynthesis in vitro in glands of low, but not in glands of high, activity. Thus, earwig brain extract after HPLC separation has Dip-AST-like material that inhibits cockroach corpora allata and suppresses earwig hindgut contractions. Sep-Pak-extracted earwig brain material, however, does not inhibit earwig gut contraction. Although synthetic Dip-AST 7 does not inhibit juvenile hormone synthesis by earwig corpora allata, there is heat-stable material in earwig brain extract that does have this action.     

The effect of juvenile hormone on protein synthesis in the transparent accessory gland of male Rhodnius prolixus

Feeding stimulates the accumulation of protein by the transparent accessory reproductive glands (TARG), allatectomy abolishes the increase, and severing the nervous connections between the corpus allatum (CA) and the brain raises the level of accumulation after feeding. TARG removed from allatectomised females exhibit a markedly decreased level of incorporation of [³H]-leucine into protein in vitro, and topical application of juvenile hormone (JH) to allatectomised males restores the ability of the glands to incorporate [³H]-leucine in vitro. Severing the nerves between the CA and the brain increases the rate of incorporation in vitro, but in both operated and normal males, the rate of incorporation decreases with time after feeding. JH applied topically to intact animals during the falling phase of incorporation, or applied directly to TARG in vitro from such animals, stimulates incorporation. These data indicate that JH from the CA controls protein synthesis in the TARG and that the CA in the male of Rhodnius may be subject to different controls than in the female.     

挥发性信息化合物对玉米螟赤眼蜂寄主选择行为的影响

在实验室条件下,利用“Y”型嗅觉仪测定了源于寄主亚洲玉米螟Ostrinia furnacalis (Guenée) 鳞片、卵表以及不同生理阶段的雌蛾附腺的不同浓度的提取物对玉米螟赤眼蜂Trichogramma ostriniae Pang et Chen寄主选择行为的影响,并对其引诱作用大小进行了比较。结果表明： 亚洲玉米螟鳞片的正己烷提取物在0.5 mg/mL和 1 mg/mL浓度时对玉米螟赤眼蜂有明显的引诱作用; 寄主卵的正己烷提取物在5块卵/mL和10块卵/mL浓度时对玉米螟赤眼蜂有显著的引诱作用,而在40块卵/mL浓度时对玉米螟赤眼蜂有极显著的驱避作用; 玉米螟赤眼蜂对亚洲玉米螟交配未产卵和产卵后前期的雌蛾附腺提取液有反应,而对处女蛾和产卵后期的附腺提取液没反应。卵表提取物和附腺提取物比鳞片提取液对赤眼蜂引诱作用强,两者对赤眼蜂的引诱作用没有明显差异。     

A comparison between the dermal glands in two insects Rhodnius prolixus (Hemiptera) and Calpodes ethlius (Lepidoptera)

The results of histochemical tests performed on the type “B” dermal gland in Rhodnius and the Verson's gland in Calpodes at different stages in their secretory cycle are presented. The secretions of both glands are slightly acidic sulphated mucosubstances. They differ in their main carbohydrate component which in Rhodnius is hyaluronic acid and in Calpodes is sialic acid. The glands, though structurally similar, differ in size, number, and development.     

Methyl farnesoate binding proteins in tissues of the spider crab, Libinia emarginata

Methyl farnesoate (MF) binding proteins (MFBPs) were found in the ovaries, testes, accessory glands, and hemolymph of the spider crab Libinia emarginata, by photoaffinity labeling the tissues in vitro with tritiated farnesyl diazomethyl ketone ([3H]-FDK). Specificity was demonstrated by competitive displacement of [3H]-FDK with MF. SDS-PAGE followed by fluorography revealed several labeled proteins in the hemolymph and testes with molecular masses ranging from 29 to 116 kDa, and two in the ovary that were 97 and 70 kDa. Tissues from reproductive animals bound twice as much label per gram weight compared to those that were from non-reproductive crabs.     

Trehalase from the bean-shaped accessory glands and the spermatophore of the male mealworm beetle,Tenebrio molitor

Summary InTenebrio molitor, male adults transfer sperm to the female via a spermatophore or sperm sac. The spermatophore is formed from secretions of the bean-shaped accessory glands (BAGs) and the tubular accessory glands (TAGs) of the male beetle. Trehalase is found in the adult BAGs. During the pupal stage, the activity in the BAGs was very low. After adult ecdysis, the total activity increased 100-fold from 0 days to 6 days and reached maximum levels at 9 days. The specific activity increased 20-fold from the time of ecdysis to 6 days thereafter. In the 10 day adult, trehalase levels in testes, seminal vesicles, vas deferens, TAGs, or ejaculatory ducts, were lower by two orders of magnitude than in the BAGs. However, the specific activity in the spermatophore was similar to that in the BAGs. Trehalases in the BAGs and the spermatophores showed very similar properties (soluble, optimum pH of 5.75 andK _m value of 5.4 mM for trehalose). Thus trehalase appears to be secreted from the BAGs and becomes incorporated into the spermatophores.Abbreviations BAG bean-shaped accessory gland - TAG tubular accessory gland     

Anatomic,Histologic and Certain Enzymatic Studies on the Male Genital Organs of Hemiechinus auritus collaris Gray,the Indian Long Eared Hedgehog

Anatomically the male reproductive organs of Hemiechinus auritus collaris are of considerable interest and present a unique pattern of arrangement of different glands. The testes are inguinal and a true scrotum is absent. A pair of accessory glands, the seminal vesicles, are situated dorsal to the bladder. A pair of obviously lobulated glands, ventral to the bladder, represent the internal prostate and a pair of compact glands situated outside the pelvis in para-anal position the external prostate. The Cowper's gland and the gland of ampulla are absent. The present studies also concern enzymes of the phosphatase group, including both specific and non-specific phosphatases, in the testes and the sex accessory glands during both active and inactive periods in this insectivore.     

Differing amounts of genetic polymorphism in testes and male accessory glands ofDrosophila melanogaster andDrosophila simulans

We surveyed genetic polymorphism by two-dimensional gel electrophoresis of male reproductive tract proteins in 20 isofemale lines each ofDrosophila melanogaster andDrosophila simulans. After classifying 244 such proteins ofDrosophila melanogaster and 271 ofDrosophila simulans by their distribution between testes and accessory glands within the reproductive tract, significant correlations were found between genetic polymorphism and tissue distribution. In both species, gland-specific proteins were significantly more polymorphic than testis-specific proteins, as well as those found in both testes and glands. Simultaneously, inDrosophila simulans, proteins found in roughly equivalent relative abundance in both testes and glands were significantly less variable than gland-specific and testis-specific proteins, as well as those with a quantitative difference in relative abundance between testes and glands. These correlations may reflect general differences in variability between extracellular and intracellular proteins and between proteins with broad as opposed to tissue-specific distributions.We thank the Natural Sciences and Engineering Research Council of Canada for financial support (Grant A0235 to R.S.S.).     

Variation in male body size and reproductive allocation in the leafcutter ant <Emphasis Type="Italic">Atta colombica</Emphasis>: estimating variance components and possible trade-offs

Remarkably little is known about the traits that determine reproductive success of males in eusocial insects. Their window for mate choice decisions is very short, the actual mating process is very difficult to observe, and their small body sizes have likely prevented systematic studies in many species. In 2008 and 2009, we revisited a Panamanian population of Atta colombica leafcutter ants to partially repeat and complement a study of more than 15 years ago. We compared within- and between-colony variation in male body size (mass and width of head, mesosoma and gaster) and sperm characteristics (length, number and survival after exposure to saline buffer with and without added accessory gland secretion). We also measured the size of accessory glands as the main contributor of seminal fluid and the accessory testes containing all mature sperm, but we found few correlations between these variables. We also obtained little or no evidence for expected trade-offs between sperm number and sperm length and between mesosoma mass and sperm complement, although this could be due to limited sample size and unknown variation in larval resource allocation that was beyond our control. However, we found an interestingly bimodal distribution in broad-sense heritabilities (intra-class correlations) among the variables that we measured. Low heritabilities suggest that mesosoma size (mass and width), accessory testes size, sperm viability (measured as % survival in saline) and probably also accessory gland size are traits directly correlated with reproductive success. However, the much higher heritabilities for total body mass, gaster mass, head width, sperm length and sperm number suggest that these traits are less likely to make direct contributions to male fitness.     

The role of male accessory-gland substance on female reproduction with some observations of spermatogenesis in the stable fly

The bulbous tubular portion of the median ejaculatory duct functions as the accessory gland in the male stable fly, Stomoxys calcitrans. The gland started to enlarge after emergence when the fly was fed on sugar-water or blood. Implants of accessory glands from sugar-water or blood-fed males were effective in stimulating oviposition in virgin females. The injection into females of accessory-gland extracts from males fed blood prevented insemination; this extract was effective in concentration as low as 0.25 gland per female. Accessory-gland extracts from sugar-water fed males were only partially effective in preventing female insemination. However, the accessory-gland extracts of male stable flies had little effect on insemination when injected into three other species of female dipterans.Spermatogenesis was completed by the time of emergence, or shortly thereafter, a process independent of blood feeding. Three types of spermatids were identified, forming a continuum of spermiogenesis stages. Fat, fusiform spermatozoa elongated to become thin, elongate and mature spermatozoa.     

Effects of water hyacinth Eichhornia crassipes root extracts on midge Chironomus ramosus larvae: a preliminary note

The effects of crude root extracts of Eichhornia crassipes (Marts) Solms on Chironomus ramosus Chaudhuri eggs and larvae are studied under laboratory conditions. Egg masses of C. ramosus that are subjected to varying concentrations of exudates (final concentrations 0.25–2.5%) show 100% viability. However, larvae reared further at these concentrations reveal a dose–response relationship, with an LC₅₀ value of 1.33% and an LC₉₀ value of 2.05%. A striking feature is the occurrence of supernumerary salivary glands in larvae (three glands per larva) reared in the 1%, 1.25%, 1.5% and 1.75% extracts. This deviates from the normal two glands per larva and may be explained by altered growth as a result of the putative bioactive compounds present in the hyacinth extracts. In nature, hyacinth and midges co‐exist in many freshwater habitats, implying that hyacinth compounds present from natural leaching could be encountered by the larvae. These preliminary findings suggest that hyacinth can influence the larval development of midges, giving rise to long‐term ecological implications.     

Male age and strain affect ejaculate quality in the Mexican fruit fly

Aging in all organisms is inevitable. Male age can have profound effects on mating success and female reproduction, yet relatively little is known on the effects of male age on different components of the ejaculate. Furthermore, in mass‐reared insects used for the Sterile Insect Technique, there are often behavioral differences between mass‐reared and wild males, while differences in the ejaculate have been less studied. The ejaculate in insects is composed mainly of sperm and accessory gland proteins. Here, we studied how male age and strain affected (i) protein quantity of testes and accessory glands, (ii) the biological activity of accessory gland products injected into females, (iii) sperm viability, and (iv) sperm quantity stored by females in wild and mass‐reared Anastrepha ludens (Diptera: Tephritidae). We found lower protein content in testes of old wild males and lower sperm viability in females mated with old wild males. Females stored more sperm when mated to young wild males than with young mass‐reared males. Accessory gland injections of old or young males did not inhibit female remating. Knowledge of how male age affects different ejaculate components will aid our understanding on investment of the ejaculate and possible postcopulatory consequences on female behavior.     

Morphological changes in the male accessory glands and testes in Vespula vulgaris (Hymenoptera,Vespidae) during sexual maturation

Abstract. The present study documents the pace of accessory gland and testes degeneration in the wasp Vespula vulgaris by means of a histological and metric approach, that has not been carried out for social wasps so far. To a certain extent, comparison is made with the degenerative processes of the mucus glands of the honeybee drone. In V. vulgaris, no generative tissue is left by the end of 9 d of age, and so degeneration is a fast process. The three different parts of the accessory glands (muscle layer, gland epithelium, and lumen) change with respect to age. The secretory cells of the epithelium reach their maximum activity during the first days of adult life, which results in a maximally filled gland lumen by 9 d. We also provide, for the first time, a histological study of testes degeneration for this species. At eclosion, well‐defined cystic structures are still visible, whereas at 9 d, it is no longer possible to distinguish different cystic structures. The diameter of the testes decreases with respect to age.     

Anatomy and histology of the male reproductive system of the fire ant,Solenopsis invicta Buren (Hymenoptera : Formicidae)

The male reproductive system of the fire ant, Solenopsis invicta Buren (Hymenoptera : Formicidae), consists of the testes, vasa efferentia, vasa deferentia, seminal vesicles, accessory glands, ejaculatory duct, wedge, aedeagal bladder, and external genitalia. The testes in newly eclosed males appear as 4 large white lobes filled with packets of sperm. Each lobe of the testes contains only one follicle. As the testes degenerate, the maturing sperm migrate through the vasa efferentia and vasa deferentia into the seminal vesicles. The seminal vesicles attach to the accessory glands, which are lined with secretory columnar epithelium. The posterior ends of the accessory glands taper and unite to form the ejaculatory duct. A sclerotized wedge is found at the junction of the accessory glands and the ejaculatory duct. An aedeagal bladder, joining the ejaculatory duct posterior to the wedge, is lined with squamous epithelium enveloped by heavy musculature. The ejaculatory duct continues posteriorly to form a distal aedeagus surrounded by 3 pairs of valves, comprising the external genitalia.     

Trehalase in the spermatophore from the bean-shaped accessory gland of the male mealworm beetle,Tenebrio molitor: purification,kinetic properties and localization of the enzyme

Trehalase from the bean-shaped accessory glands of the male mealworm beetle, Tenebrio molitor, was purified by acid treatment, with subsequent chromatography on columns of DEAE-cellulofine and Sephacryl S-300. The molecular masses of the native and the denatured forms were estimated to be 43 and 62 kDa by gel filtration and SDS-PAGE, respectively, an indication that the trehalase may be composed of a single polypeptide. The optimum pH of the reaction catalyzed by trehalase was 5.6–5.8. The K _m for trehalose was 4.4 mmol·l^–1. Immunohistochemical experiments with trehalase-specific antiserum showed that the enzyme was localized in one specific type of secretory cell in the bean-shaped accessory gland epithelium and within the semisolid secretory mass that was a precursor to the wall of spermatophore. SDS-PAGE and immunoblotting analysis revealed the presence of a polypeptide of about 62 kDa in the spermatophore, Immunohistochemical observations showed that the trehalase was located at the outgrowth in the anterior portion of the spermatophore. When a fresh spermatophore was immersed in phosphate-buffered saline it discharged sperm in the same manner as in the bursa copulatrix of the female. Before the rupture of the expanded bulb of the spermatophore, almost all of the trehalase had dissolved in the phosphate-buffered saline. The addition of validoxylamine A to the saline, a specific inhibitor of trehalase, did not affect the expansion and evacuation of the spermatophore. These results demonstrate that trehalase, synthesized by a specific type of secretory cell in the bean-shaped accessory gland epithelium, is actively passed into the lumen of the bean-shaped accessory gland and then incorporated into the spermatophore. Trehalase appears to be one of the structural proteins of the spermatophore, although the possibility can not yet be completely ruled out that the trehalase-trehalose system functions for the nourishment and/or activation of the sperm in the bursa copulatrix of the female.Abbreviations BAG bean-shaped accessory gland(s) - DEAE diethylaminoethyl - Kpi buffer K₂HPO₄/KH₂PO₄ buffer (pH 7.0) - PAGE polyacrylamide gel electrophoresis - PBS phosphate-buffered saline - SDS sodium dodecy sulphate - Spph spermatophore(s) - TAG tubular accessory gland(s)     

Mating senescence and male reproductive organ size in the Mexican fruit fly

Ageing can reduce the probability that individuals reproduce. The present study investigates whether ageing influences the mating frequency of mass‐reared fertile and sterile Mexican fruit flies Anastrepha ludens (Loew). The ability of males of different ages to inhibit female remating is also determined, and the growth of male reproductive organs is measured as they age. Young males (6 days old) have a lower mating frequency than older males, and also have a lower capacity to inhibit female remating than older males. However, 7‐day‐old males are as likely to inhibit female remating as older males. Young males also have smaller reproductive organs than middle‐aged (21‐day‐old) or senescent males (57‐day‐old). These results have implications for the sterile insect technique because sterilized males of A. ludens are released in the field 6 days after emergence. The highest mating frequency, the lowest mating latency and the largest size of testes are observed at 21 days of age. Older males (57 days old) have more sperm in their seminal vesicles than young males (6 and 9 days old). Accessory glands take longer to grow to their complete size compared with testes, and mating frequency is more closely associated with accessory gland size than testes size. Furthermore, there are more sperm in the seminal vesicles during the afternoon period of peak sexual activity than during the morning when sexual activity is absent. These results indicate that, even at the onset of reproductive senescence, mass‐reared males of A. ludens are still capable of mating, as well as inhibiting remating in females.     

Lactate dehydrogenase C4 in male sex accessory glands of normal mice and in testes of sex-reversed mice.

Lactate dehydrogenase (LDH) C4 activity was observed in testis extracts of sex-reversed mice (Sxr) and in male sex accessory gland (seminal vesicle and prostate) extracts from C3H/He and C57BL/Go mice. These results reflect either (1) the presence of low concentrations of germinal cells in these tissues; or (2) the synthesis of LDH-C4 by somatic cells in Sxr testes and normal male sex accessory glands.     

Testes of fed and unfed Amblyomma cajennense ticks (Acari: Ixodidae). First morphological data

The tick species Amblyomma cajennense is of great medical importance, as it is the vector of the Rickettsia rickettsii, agent of Rocky Mountain spotted fever. The objective of this study was to perform a morphological and histological analysis of the male reproductive system of fed and unfed A. cajennense. The male reproductive system is formed by a pair of tubular testes dorsolaterally arranged in opisthosoma. They were divided into three regions: proximal region (next to vas deferens), median region and distal region (nearest to the blind ending of testis). Proximal regions are connected to the seminal vesicles by the deferent ducts and to accessory glands, similar to what was observed for other Ixodidae. Feeding plays a fundamental role in the development of the reproductive system, as in unfed individuals, the testes, the seminal vesicles and the accessory glands were smaller comparing with the fed individuals. In addition, the prospermia, precursors of the spermatozoa, were only observed in fed individuals. The germ cells were organized in spermatocysts, enveloped by a connective tissue. The cells in more advanced stages of spermatogenesis were localized in the distal region, in accord with studies in other ticks, but opposite to what was observed for other arthropods.