Development of secretory ability in the spermatheca of the migratory grasshopper, Melanoplus sanguinipes

During the first week of adult life, the protein content of the spermatheca increases by about 45% but the carbohydrate content does not change significantly. Incorporation of radiolabelled leucine into protein is high in newly emerged females but by day 1 has declined to about two-thirds the initial level, where it then remains. With SDS-PAGE about 30 protein bands separate, including six glycoprotein fractions. All bands are present throughout sexual maturation and except for one (at 25 Kd), show little change in quantity during this period. Allatectomy or hormone replacement therapy has little effect on the parameters measured and it is concluded that the development of secretory activity in the spermatheca is not controlled by juvenile hormone.     

Extraglandular synthesis of accessory reproductive gland components in male Melanoplus sanguinipes

The accessory reproductive glands (ARG) of the male migratory grasshopper, Melanoplus sanguinipes, are able to accumulate injected labelled ARG protein from the haemolymph. Accumulation is slight in the ARG of 2-day-old virgins, or 7-day-old allatectomized (CA^?) insects. The ARG of 7-day-old virgins, or 7-day-old CA^? insects treated with synthetic juvenile hormone, accumulate about 1.5 times more label than those of 2-day-old insects in a 24-hr period. The ARG of recently mated males accumulate almost four times more label than those of 2-day-old controls. Immunoprecipitation studies indicate that about one fifth of the labelled protein is accumulated unchanged.The fat body and haemolymph contain proteins which are precipitable by antiserum to whole ARG homogenate. The concentration of these proteins in the fat body increases after removal of the ARG, or after copulation. It is concluded that the fat body synthesizes certain proteins which are accumulated by the ARG. Both the synthesis and the accumulation of these proteins are regulated by the corpora allata.     

Development of accessory reproductive glands and its control by the corpus allatum in adult male Melanoplus sanguinipes

Changes in the protein content of and the rate at which labelled protein appears in the accessory reproductive glands (ARG), fat body, and haemolymph were studied in normal and allatectomized (CA^?) males of the migratory grasshopper, Melanoplus sanguinipes. In addition, the effects of treatment of CA^? insects with synthetic juvenile hormone (SJH), copulation, and removal of the ARG were examined.In normal males the protein content of the ARG increases linearly during the first 14 days after emergence. Incorporation of label by the ARG is maximal at day 7 and then decreases until, at day 14, it is the same as at day 1. The protein content of the fat body and haemolymph increases up to day 10 then declines, whereas changes in the uptake of label by the fat body and haemolymph parallel those of the ARG.Removal of the corpora allata (CA) prevents the normal increase in protein content of the ARG, but the protein content of the fat body and haemolymph increases steadily throughout the 14 days. Incorporation of label into the ARG, fat body, and haemolymph remained low throughout the experiment. Treatment of CA^? insects with SJH, or copulation, stimulates the uptake of label by the ARG, fat body, and haemolymph and also results in an increase in their protein content.Removal of the ARG leads to an increase in the protein content of the fat body and haemolymph. Uptake of label by the fat body remains low after the operation. Although the rate at which labelled protein appears in the haemolymph is high initially, it declines steadily to day 14.We conclude that the CA regulate ARG development. It is suggested that the fat body, under CA control, synthesizes proteins which are incorporated into secretions of the ARG. Further, it is proposed that the primary effect of copulation is activation of the CA.     

The neuro-endocrine control of protein metabolism in the migratory grasshopper, Melanoplus sanguinipes

In normal females, distinct fluctuations in the protein content of the fat body and haemolymph are evident during each gonotrophic period. These fluctuations partly reflect changes in the protein requirements of the developing oocytes. Almost one half of the total protein deposited in the mature ovary is sequestered during the final stages of vitellogenesis when protein accumulated in the fat body and haemolymph is rapidly depleted. Although similar amounts of protein are deposited in the ovary during the first and subsequent gonotrophic periods, significantly less extraovarian protein is present throughout the latter periods.The accumulation of large amounts of protein in the fat body and haemolymph of ovariectomized females suggests that most yolk protein is of extraovarian origin. As the total protein content of these insects is comparable to that of vitellogenic females, ovariectomy apparently has no immediate effect on protein synthesis.Allatectomy or cautery of the median neurosecretory cells (mNSC) prevents vitellogenesis. Although protein gradually accumulates in the fat body and haemolymph of allatectomized females, the total protein content of these insects is significantly lower than that of controls. Treatment of allatectomized females with juvenile hormone analogue leads to a temporary but significant increase in the protein content of the fat body. However, the subsequent decline in fat body protein is paralleled by a pronounced increase in the protein content of the ovary. These findings suggest that the corpora allata (CA) stimulate both yolk protein synthesis in the fat body and its uptake into the ovary. The total protein content of mNSC-cauterized females is less than that of allatectomized females. This observation supports the proposal that the mNSC have not only an allatotropic effect but also a direct effect on protein synthesis.     

Male insect accessory glands: Functions and control of secretory activity

Summary

Paralleling the diversity of the class Insecta, the male accessory glands (MAG) exhibit a wide range of form, and their secretion serves a variety of functions, including spermatophore and mating plug formation, sperm activation, provision of nutrients to females, and, through production of fecundity-enhancing and/or receptivity-inhibiting substances, modification of female reproductive behavior. In most insects, juvenile hormone (JH) is important in the regulation of MAG secretory activity; specifically, JH controls the production of particular proteins in the secretion. However, the production of some proteins appears not to be influenced by JH; rather, their synthesis is regulated by ecdysteroids. During sexual maturation, JH and ecdysteroids seem to interact to bring about a specified temporal sequence of protein synthesis in the MAG.     

An electrophoretic study of proteins of the ovary,fat body,and haemolymph in the migratory grasshopper, Melanoplus sanguinipes

Electrophoretic separation of saline extracts from the ovary revealed 14 proteins. Twelve proteins were detected in the fat body, of which seven had electrophoretic mobilities identical to those in the ovary. Similarly, eight of 16 proteins in the haemolymph of vitellogenic females ahad electrophoretically identical counterparts in the ovary. As these proteins accumulate in the haemolymph of ovariectomized females, the findings suggest that most yolk proteins are synthesized in the fat body. Although most female haemolymph proteins are present in males, two of the predominant yolk protiens are absent and represent female-specific proteins.Although certain proteins accumulate in the haemolymph of allatectomized females, the major ovarian proteins are absent or present in low concentrations. However, 48 hr after allatectomized females are treated with a juvenile hormone analogue, the haemolymph protein pattern resembles that of a normal female. This suggests that the corpora allata stimulate the synthesis of female-specific and other vitellogenic proteins. The median neurosecretory cells (mNSC) are also necessary for synthesis of female-specific proteins. Furthermore, proteins which are present in allatectomized females are absent in mNSC-cauterized insects suggesting that the mNSC stimulate general protein synthesis.     

Evidences of the extraglandular origin of two secretory proteins in the male accessory reproductive glands of Chilo partellus (Pyralidae,Lepidoptera, Insecta)

Summary

The male accessory reproductive glands (MARG) play an important role in contributing proteins for the formation of the spermatophore, a structure that transports sperm from the male to the female. Several studies have shown that these proteins could be either of intraglandular or extraglandular origin. SDS-PAGE analysis revealed proteins in the adult MARG of Chilo partellus, which comigrate with the larval hemolymph proteins (LHP). Ouchterlony's immunodiffusion showed that the antiserum raised against MARG extract cross-reacts with the proteins present in the adult hemolymph and fat body. Immunoprecipitates of labelled hemolymph proteins with anti-LHP or anti-MARG proteins reveal two polypeptides that comigrate with LHPs. Thus, there appear to be some proteins of extraglandular origin in the MARG of C. partellus, and the LHP could belong to this category.     

Structure of the accessory reproductive glands of the male migratory grasshopper,Melanoplus sanguinipes

The accessory reproductive glands of Melanoplus sanguinipes comprise two bilateral masses of 16 tubules each, distinguishable in sexually mature insects as four white, ten short hyaline, one long hyaline, and a seminal vesicle. Over most of its length, the wall of each tubule consists of a simple glandular epithelium resting on a basal lamina, surrounded by a thin layer of circular muscle. However, near the junction with the ejaculatory duct, the wall of each tubule has a much thickened circular muscle layer and squamous or cuboidal epithelium, the region serving to regulate movement of secretion into the ejaculatory duct. Interdigitation of adjacent epithelial cells is common, and several kinds of specialized junctions occur. In the glandular region, all epithelial cells appear the same and may be flattened, cuboidal, or columnar depending on the tubule type. Except for those of the seminal vesicle, the glandular epithelial cells share ultrastructural features typical of cells engaged in the synthesis of protein for export. Despite these general similarities, in most instances subtle differences occur in the cellular ultrastructure of the epithelia of each tubule and in the appearance of their luminal secretions, suggesting that the tubules are functionally specialized.     

The ultrastructure of the male accessory reproductive glands of the colorado beetle

Summary The accessory reproductive glands of Leptinotarsa decemlineata males are simple epithelial tubular glands. They are surrounded by a network of slow acting muscle cells. All the gland cells have a very extensive granular endoplasmic reticulum, a prominent Golgi apparatus, but few secretory granules. The secretory product in the lumen, which is a neutral mucopolysaccharide-protein complex, appears as a granular material in which fibrillar structures occur. Neither in the gland cells nor in the lumen were regional differences observed. After allatectomy the gland cells degenerate in a remarkable way. A zone containing microvillous structures appears between the outer and inner cells. While the inner cells degenerate completely, the outer ones do not but become organised for minimal consumption of energy, necessary to survive diapause.Grateful acknowledgment is made for a mandate as Aangesteld Navorser of the National Foundation of Scientific Research in Belgium.We wish to thank Ing. W. Bohijn for operating the EM and Mr. G. Maes for photography.     

Juvenile hormone regulation of male accessory gland activity in the red flour beetle, Tribolium castaneum

Male accessory gland proteins (Acps) act as key modulators of reproductive success in insects by influencing the female reproductive physiology and behavior. We used custom microarrays and identified 112 genes that were highly expressed in male accessory glands (MAG) in the red flour beetle, Tribolium castaneum. Out of these 112 identified genes, 59 of them contained sequences coding for signal peptide and cleavage site and the remaining 53 contained transmembrane domains. The expression of 14 of these genes in the MAG but not in other tissues of male or female was confirmed by quantitative real-time PCR. In virgin males, juvenile hormone (JH) levels increased from second day post adult emergence (PAE), remained high on third day PAE and declined on fourth day PAE. The ecdysteroid titers were high soon after adult emergence but declined to minimal levels from 1 to 5 days PAE. Feeding of juvenile hormone analog, hydroprene, but not the ecdysteroid analog, RH-2485, showed an increase in size of MAGs, as well as an increase in total RNA and protein content of MAG. Hydroprene treatment also increased the expression of Acp genes in the MAG. RNAi-mediated knock-down in the expression of JHAMT gene decreased the size of MAGs and expression of Acps. JH deficiency influenced male reproductive fitness as evidenced by a less vigor in mating behavior, poor sperm transfer, low egg and the progeny production by females mated with the JH deficient males. These data suggest a critical role for JH in the regulation of male reproduction especially through MAG secretions.     

Ultrastructure and nature of secretory proteins in the male accessory gland of Drosophila funebris

The ultrastructural differentiation of the secretory cells and the nature of secretory proteins in the male accessory gland of Drosophila funebris have been studied by electron-microscopic and immunological methods. (1) In the pupae at $\text{1}\text{1}\text{2}$ days before eclosion, secretory products can be detected in the lumen, even though most glandular cells are at the initial phase of differentiation. At the time of eclosion both main and secondary cells are fully differentiated, but the whole set of five immunologically active proteins are detectable only on the second to third day of adult life. (2) The secondary cells contain giant protein granules, the so-called filamentous bodies, which become partially fused and the filaments assume a twisted form. Randomly dispersed filaments and closely packed filament bundles are also visible in the gland lumen. Antigenic labelling of ultrathin sections and immunoreplica electrophoresis yielded no evidence for the microtubular nature of these filaments. The secretion stored in the lumen contains in addition a large quantity of flocculent proteins which have their origin in the main cells. (3) During the period of high secretory activity in the 7-day-old male flies no vacuolization and disintegration of either the main or secondary cells have been observed. We conclude that both types of cells have the merocrine secretory mechanism. (4) Ultrastructural alterations in the glandular cells confirmed our previous observation that copulation stimulates RNA and protein synthesis.     

Sonomorphology of the reproductive tract in male and pregnant and non-pregnant female Rothschild's giraffes (Giraffa camelopardalis rotschildi)

The application of real-time-B-mode ultrasonography to wild and zoo animal medicine has been shown to improve the understanding of reproductive physiology in many species. Ultrasound technology is especially helpful for monitoring urogenital health, which in turn has advantages for giraffe breeding and welfare in captivity.This study aimed to ultrasonographically describe the genital organs of reproductively healthy male and female giraffes. Through the use of a restrainer, repeated rectal ultrasound examinations were performed over a 2 year period in 2.6 Rothschild's giraffes. Changes in ovarian activity were monitored throughout four different reproductive stages in the females and included immature, mature-cycling, pregnancy, post-partum-period. In the immature giraffes the ovaries showed multiple follicles of which larger ones luteinized to form pseudo-corpora lutea. By comparison, in the mature giraffes the dominant follicle reached an ovulatory diameter of 18.5 ± 0.89 mm. After ovulation, a single corpus luteum rapidly formed and reached a maximum diameter of 33.0 ± 2.4 mm on average. Pregnancy was detected for the first time by the embryonic vesicle, visualized around 28 days post copulation. Follicular development remained ongoing during early pregnancy. In the males, as in other ruminants, the bulbourethral glands and the seminal vesicles were prominent, whereas the prostate gland was indistinct.Knowledge about the reproductive tract morphology and physiology is necessary for diagnosing medical disorders and abnormalities in giraffes. The aim of this study was to help consolidate the current knowledge on basic reproductive parameters for this species.     

Morphology of reproductive accessory glands in female Sepia pharaonis (Cephalopoda: Sepiidae) sheds light on egg encapsulation

The pharaoh cuttlefish, Sepia pharaonis, is an important cephalopod fishery species in southeastern Asia, with understudied reproductive physiology. The present study aimed to investigate the cellular characteristics of epithelial cells found in the nidamental glands (NGs) and accessory NGs (ANGs), as well as the structural connections between these two glands in mature female S. pharaonis. A histological analysis revealed two types of epithelial cells in NGs: Alcian blue‐positive, PAS‐negative mucosubstance‐secreting cells and eosinophilic, PAS‐positive granule‐secreting cells. Using transmission electron microscopy, three types of epithelial cells were identified: cells with electron‐dense granules, cells with electron‐lucent granules, and cells with both cilia and microvilli in the apex. Mature ANGs contain an abundance of tubular units composed of epithelial cells resting on a thin layer of basal lamina. Innervated muscle cells are tightly adhered to the basal lamina. In addition, we observed epithelial canalization of ANG tubules penetrating through the connective tissue linking NGs and the walls of the tubules in ANGs, which allows the contents of the ANG tubules to be transported to the NGs. Our results suggest that ANGs participate in the encapsulation of the ova via the same pathway as NGs, which provides an important basis for future studies on the mechanism of protection provided by NGs and ANGs during embryonic development in S. pharaonis.     

A polypeptide from male accessory glands which triggers maturation of tick spermatozoa

The maturation of tick (Acari: Ixodoidea) spermatozoa, after their transfer to the female, is induced by secretions of the male accessory gland which are added to the prospermia during ejaculation. Analysis of the secretions from male Ornithodoros moubata (Argasidae) and Dermacentor variabilis (Ixodidae) indicates that the factor responsible for inducing maturation is a polypeptide with a molecular weight of about 12,500. Although the polypeptides from the two species are similar in most respects, each will not activate the prospermia of the other species. The mode of action of the factor is hormone-like, inasmuch as a few minutes of exposure of the sperm to the factor are sufficient to trigger the entire maturation sequence, which takes 12–24 h in vitro.     

Improved assay conditions for measurement of corpus allatum activity in vitro in the adult Colorado potato beetle, Leptinotarsa decemlineata

Assay conditions for the short-term, radiochemical, in vitro determination of the spontaneous rate of juvenile biosynthesis by isolated corpora allata from Leptinotarsa decemlineata have been further improved, permitting the measurement of juvenile hormone biosynthesis by individual pairs of corpora allata. The final incubation product has been identified as juvenile hormone III with the aid of High-performance liquid chromatography (HPLC) and juvenile hormone esterase degradation. Using the new assay conditions, the activities of adult corpora allata during maturation were found to be significantly higher in reproductive, long-day animals than in pre-diapause, short-day beetles. During diapause no activity was detectable, whereas corpora allata from post-diapause beetles were reactivated totally after 5 days. Simultaneous determination of the in vitro rates of juvenile hormone biosynthesis and corpus allatum volumes revealed no clear correlation although the results suggest that the volume may be indicative of the maximal capacity for juvenile hormone production. Corpora allata from a population of beetles did not display any synchronous diurnal rhythmicity.     

Corpus al latum regulation of copulatory behaviour in the male grasshopper, Melanoplus sanguinipes

Abstract The relationship between corpus allatum (CA) regulation of copulatory behaviour and the CA's influence on the development of the accessory reproductive glands was studied in the male grasshopper, Melanoplus sanguinipes (Fabr.). Allatectomy slowed the development of copulatory behaviour; ≤80% of control males 7 days and older mated with females, but allatectomized males did not show comparable levels of copulation until day 19. In a 3 h observation period, the time taken for 50% of males to initiate copulation was c. 60 min for allatectomized males and only c. 10 min for controls. At the age when 50% of males copulated, the accessory glands of allatectomized males were less developed than those of controls; the accessory gland weight was 65%, soluble protein was 72% and reserves of long hyaline protein I were 40% those of controls. Treatment with Juvenile Hormone III on day 2 stimulated accumulation of long hyaline protein I in 9-day-old allatectomized males to the level found in untreated 19-day-old allactec-tomized males, but did not elicit heightened copulation. No positive feedback from the accessory glands appeared necessary to elicit copulation since vasectomy, ablation of the accessory glands or isolation of the terminal abdominal ganglion by ventral nerve cord transection did not inhibit copulatory behaviour in 7-day-old males. Because allatectomy inhibited copulatory behaviour in 7-day-old males in which the accessory glands were removed but not in 19-day-old males without accessory glands, the increased tendency of older allatectomized males to mate with females was not due to release of inhibition caused by continued growth of the accessory reproductive glands.     

Structural proteins of Amsacta moorei,Euxoa auxiliaris, and Melanoplus sanguinipes entomopoxviruses

The structural proteins of Amsacta moorei, Euxoa auxiliaris, and Melanoplus sanguinipes entomopoxviruses (EPVs) were separated by electrophoresis on sodium dodecyl sulfate (SDS)-polyacrylamide gels. More than 35 structural proteins were detected in each virus. Based on the distribution and the variation in the molecular weights of the virus structural proteins little homology was detected between the EPVs and vaccinia virus. The molecular weight of Amsacta EPV occlusion body matrix protein (110,000) was determined by SDS-acrylamide gel electrophoresis. The occlusion body matrix protein of Amsacta EPV occluded virus isolated from infected E. acrea larvae was rapidly degraded at pH 10.6 to peptides of approximately 94,000 and 60,000 daltons. After 2 hr incubation at alkaline pH, Amsacta EPV occlusion body protein was degraded to approximately 56,000 daltons. Proteolysis of occlusion body protein was inhibited by SDS. No proteolytic degradation was detected in occlusion body matrix protein isolated from Amsacta EPV infected BTI-EAA cells. Amino acid analysis indicates that entomopoxvirus occlusion body matrix protein consists of approximately 20% acidic amino acids and 9% of the sulfur-containing amino acids cysteine and methionine.     

Wing morph-related differences in developmental pattern of accessory gland proteins in adult males of Pyrrhocoris apterus (L.) and their endocrine control

The study showed that the amounts of the total proteins and 53 kDa protein in male accessory glands (AGs) of the firebug Pyrrhocoris apterus (L.) increased with age of the adult life. The 53 kDa protein, the most abundant polypeptide detected in the secretion of the AGs, and some other smaller peptides were identified as glycoproteins. Changes in the amounts of the total proteins and 53 kDa protein in AGs were found to be wing morph-dependent and their levels were significantly higher in 1-10 days old brachypterous males than in macropterous males of the same age. Macropterous males were characterized by delayed growth of the AGs. Treatment of adult macropterous males with methoprene significantly increased the amounts of total proteins and 53 kDa protein in their AGs when compared to acetone-treated macropterous controls of the same age. Allatectomy of brachypterous males decreased the levels of the total proteins and 53 kDa protein in their AGs, while application of methoprene enhanced the quantity of allatectomy-suppressed proteins in these tissues. This is the first report of juvenile hormone-dependent wing morph-related differences in the synthesis of AG proteins and their endocrine control in wing-polymorphic insects.     

Trehalases from the American cockroach,Periplaneta americana: multiple occurrence of the enzymes and partial purification of enzymes from male accessory glands

Trehalase activities were found in several tissues of the adult American cockroach, Periplaneta americana. Among these, male accessory glands, fat body, thoracic muscle, hepatic cecum, blood and mid-gut contained high trehalase activity; activity in the male accessory gland was especially high. The enzymic properties of soluble trehalases were investigated and the enzymes from the male accessory gland were highly purified.

The properties of these enzymes were electrophoretically and kinetically distinct from each other. The presence of enzymes with somewhat different properties in different tissues suggests that trehalose utilization and trehalase activity may be regulated by way of a tissue-specific mechanism. The detailed properties of these enzymes are presented with a discussion of their regulation.