<i>In vitro</i>synthesis of ecdysteroid by the male accessory reproductive glands, testis and abdominal integument of the adult migratory grasshopper,<i>Melanoplus sanguinipes</i>

Gillott, Cedric; Ismail, Preeti M.

doi:10.1080/07924259.1995.9672435

Cited by 29 publications

(10 citation statements)

References 33 publications

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“…Ecdysone (E) and 20-hydroxy-ecdysone (20E) are the physiologically most relevant ecdysteroids (Lafont and Kooman, 2009; Lafont et al, 2012). In the adult stage, ecdysteroids are mainly synthesized in the gonads (Brown et al, 2009), although other tissues have been suggested as additional sources of ecdysteroids in some insect species (e.g., Delbecque et al, 1990; Gillot and Ismail, 1995). Ecdysteroids have autocrine and paracrine regulatory roles in ovary and oocyte development, since they control ovary morphogenesis, differentiation of germ line stem cells and development of follicle cells (Parthasarathy et al, 2010; Gancz et al, 2011; Konig et al, 2011; Ting, 2013).…”

Section: The Isp and Female Reproductive Physiologymentioning

confidence: 99%

Eat to reproduce: a key role for the insulin signaling pathway in adult insects

Badisco¹,

Wielendaele²,

Broeck³

2013

Front. Physiol.

136

140

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Insects, like all heterotrophic organisms, acquire from their food the nutrients that are essential for anabolic processes that lead to growth (larval stages) or reproduction (adult stage). In adult females, this nutritional input is processed and results in a very specific output, i.e., the production of fully developed eggs ready for fertilization and deposition. An important role in this input-output transition is attributed to the insulin signaling pathway (ISP). The ISP is considered to act as a sensor of the organism's nutritional status and to stimulate the progression of anabolic events when the status is positive. In several insect species belonging to different orders, the ISP has been demonstrated to positively control vitellogenesis and oocyte growth. Whether or not ISP acts herein via a mediator action of lipophilic insect hormones (ecdysteroids and juvenile hormone) remains debatable and might be differently controlled in different insect orders. Most likely, insulin-related peptides, ecdysteroids and juvenile hormone are involved in a complex regulatory network, in which they mutually influence each other and in which the insect's nutritional status is a crucial determinant of the network's output. The current review will present an overview of the regulatory role of the ISP in female insect reproduction and its interaction with other pathways involving nutrients, lipophilic hormones and neuropeptides.

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Section: The Isp and Female Reproductive Physiologymentioning

confidence: 99%

Eat to reproduce: a key role for the insulin signaling pathway in adult insects

Badisco¹,

Wielendaele²,

Broeck³

2013

Front. Physiol.

136

140

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“…Although adult males are known to produce ecdysteroids, little is known about the site of synthesis and their role in males [22]. Some studies suggest that ecdysteroid synthesis occurs in the reproductive system of adult males [23], [24], and a recent study shows that the Halloween genes are expressed in the male accessory glands of the mosquito Anopheles gambiae that likely synthesizes ecdysteroids de novo [25].…”

Section: Introductionmentioning

confidence: 99%

Accessory Gland as a Site for Prothoracicotropic Hormone Controlled Ecdysone Synthesis in Adult Male Insects

et al. 2013

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Insect steroid hormones (ecdysteroids) are important for female reproduction in many insect species and are required for the initiation and coordination of vital developmental processes. Ecdysteroids are also important for adult male physiology and behavior, but their exact function and site of synthesis remains unclear, although previous studies suggest that the reproductive system may be their source. We have examined expression profiles of the ecdysteroidogenic Halloween genes, during development and in adults of the flour beetle Tribolium castaneum. Genes required for the biosynthesis of ecdysone (E), the precursor of the molting hormone 20-hydroxyecdysone (20E), are expressed in the tubular accessory glands (TAGs) of adult males. In contrast, expression of the gene encoding the enzyme mediating 20E synthesis was detected in the ovaries of females. Further, Spookiest (Spot), an enzyme presumably required for endowing tissues with competence to produce ecdysteroids, is male specific and predominantly expressed in the TAGs. We also show that prothoracicotropic hormone (PTTH), a regulator of E synthesis during larval development, regulates ecdysteroid levels in the adult stage in Drosophila melanogaster and the gene for its receptor Torso seems to be expressed specifically in the accessory glands of males. The composite results suggest strongly that the accessory glands of adult male insects are the main source of E, but not 20E. The finding of a possible male-specific source of E raises the possibility that E and 20E have sex-specific roles analogous to the vertebrate sex steroids, where males produce primarily testosterone, the precursor of estradiol. Furthermore this study provides the first evidence that PTTH regulates ecdysteroid synthesis in the adult stage and could explain the original finding that some adult insects are a rich source of PTTH.

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“…In these cases, steroids were released by testicular follicular sheaths at the end of the last larval instar and during pupal development. Synthesis of steroids has also been observed in several tissues of adult male migratory grasshoppers (order Orthoptera) and in the testes of the adult male blowfly Calliphora vicina (order Diptera) (16,17). However, only small amounts of steroids were released in vitro when compared with the amounts produced by ovaries, and no prominent compound has been identified.…”

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confidence: 95%

Anopheles gambiaemales produce and transfer the vitellogenic steroid hormone 20-hydroxyecdysone to females during mating

Pondeville

Maria

Jacques

et al. 2008

Proc. Natl. Acad. Sci. U.S.A.

107

127

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In female insects, the steroid hormone 20-hydroxyecdysone (20E) plays a major role in activating vitellogenesis, a process required for egg development. By contrast with vertebrates, production of large amounts of hormonal steroids has not been reported in adult male insects. In the present study, we analyzed steroidogenesis in both male and female adult of the malaria mosquito Anopheles gambiae and we found that A. gambiae male mosquitoes produce high amounts of the steroid hormone 20E. Importantly, we found that male accessory glands, but not testes, are the source of 20E. Moreover, this steroid hormone is stored in male accessory glands and delivered to females during mating. These findings suggest that male 20E may not act as a true male sex steroid, but more likely as an allohormone. Our results give new insights into speciesspecific physiological processes that govern the reproductive success of the malaria mosquito. This could thus lead to the identification of new target genes for manipulating male and/or female reproductive success, a promising way to reduce or eliminate mosquito population and therefore to control malaria transmission.allohormone ͉ ecdysteroids ͉ malaria ͉ male accessory glands ͉ mosquito

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In vitrosynthesis of ecdysteroid by the male accessory reproductive glands, testis and abdominal integument of the adult migratory grasshopper,Melanoplus sanguinipes

Cited by 29 publications

References 33 publications

Eat to reproduce: a key role for the insulin signaling pathway in adult insects

Eat to reproduce: a key role for the insulin signaling pathway in adult insects

Accessory Gland as a Site for Prothoracicotropic Hormone Controlled Ecdysone Synthesis in Adult Male Insects

Anopheles gambiaemales produce and transfer the vitellogenic steroid hormone 20-hydroxyecdysone to females during mating

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