1
|
Kremer AN, King BH. A Neonicotinoid Affects the Mating Behavior of Spalangia endius (Hymenoptera: Pteromalidae), a Biological Control Agent of Filth Flies. ENVIRONMENTAL ENTOMOLOGY 2019; 48:489-495. [PMID: 30873550 DOI: 10.1093/ee/nvz015] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/21/2018] [Indexed: 06/09/2023]
Abstract
Spalangia endius Walker is a parasitoid wasp that is commercially available as a biological control agent for filth fly pests in livestock-rearing operations. Imidacloprid is often used to control these flies. The present study examined the sublethal effect of field-realistic concentrations of imidacloprid on mating behavior, offspring sex ratios, and male preference for virgin females. After exposure to imidacloprid, S. endius females that survived were less likely to mate than control females, which will result in male-biased sex ratios because only mated females can produce daughters. Males did not avoid exposed females, but exposed females were almost always unreceptive. Males that survived exposure to imidacloprid exhibited reduced mating competitiveness against unexposed males. However, if an exposed male mated, his mate's sex ratio and ability to control flies was unaffected. Exposed males were also still able to discriminate against mated, and thus usually unreceptive, females. Together with previous studies, these results suggest that not only does imidacloprid reduce the ability of S. endius females to survive and parasitize hosts, but when an exposed female does survive and parasitize hosts, she is likely to produce just sons, because of her lack of receptivity. More-male-biased populations of S. endius will decrease their efficacy for fly control. Thus, the use of imidacloprid along with this parasitoid may be financially inefficient for pest management.
Collapse
Affiliation(s)
- Aspen N Kremer
- Department of Biological Sciences, Northern Illinois University, DeKalb, IL
| | - Bethia H King
- Department of Biological Sciences, Northern Illinois University, DeKalb, IL
| |
Collapse
|
2
|
Nilsson B, Hansen BW. Timing of embryonic quiescence determines viability of embryos from the calanoid copepod, Acartia tonsa (Dana). PLoS One 2018. [PMID: 29513715 PMCID: PMC5841787 DOI: 10.1371/journal.pone.0193727] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
Like 41 other calanoid copepods, Acartia tonsa, are capable of inducing embryonic quiescence when experiencing unfavorable environmental conditions. The ecdysone-signaling cascade is known to have a key function in developmental processes like embryogenesis and molting of arthropods, including copepods. We examined the role of ecdysteroid-phosphate phosphatase (EPPase), ecdysone receptor (EcR), ß fushi tarazu transcription factor 1 (ßFTZ-F1), and the ecdysteroid-regulated early gene E74 (E74), which represent different levels of the ecdysone-signaling cascade in our calanoid model organism. Progression of embryogenesis was monitored and hatching success determined to evaluate viability. Embryos that were induced quiescence before the gastrulation stage would stay in gastrulation during the rest of quiescence and exhibited a slower pace of hatching as compared to subitaneous embryos. In contrast, embryos developed further than gastrulation would stay in gastrulation or later stages during quiescence and showed a rapid pace in hatching after quiescence termination. Expression patterns suggested two peaks of the biological active ecdysteroids, 20-hydroxyecdysone (20E). The first peak of 20E was expressed in concert with the beginning of embryogenesis originating from yolk-conjugated ecdysteroids, based on EPPase expression. The second peak is suggested to originate from de novo synthesized 20E around the limb bud stage. During quiescence, the expression patterns of EPPase, EcR, ßFTZ-F1, and E74 were either decreasing or not changing over time. This suggests that the ecdysone-signaling pathway play a key role in the subitaneous development of A. tonsa embryogenesis, but not during quiescence. The observation is of profound ecological and practical relevance for the dynamics of egg banks.
Collapse
Affiliation(s)
- Birgitte Nilsson
- Department of Science and Environment, Roskilde University. Universitetsvej 1, Roskilde, Denmark
- * E-mail:
| | - Benni Winding Hansen
- Department of Science and Environment, Roskilde University. Universitetsvej 1, Roskilde, Denmark
| |
Collapse
|
3
|
Cardinal-Aucoin M, Rapp N, Steel CG. Circadian regulation of hemolymph and ovarian ecdysteroids during egg development in the insect Rhodnius prolixus (Hemiptera). Comp Biochem Physiol A Mol Integr Physiol 2013; 166:503-9. [DOI: 10.1016/j.cbpa.2013.08.003] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2013] [Revised: 08/05/2013] [Accepted: 08/06/2013] [Indexed: 11/24/2022]
|
4
|
De Loof A, Boerjan B, Ernst UR, Schoofs L. The mode of action of juvenile hormone and ecdysone: towards an epi-endocrinological paradigm? Gen Comp Endocrinol 2013; 188:35-45. [PMID: 23454668 DOI: 10.1016/j.ygcen.2013.02.004] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/20/2012] [Revised: 02/07/2013] [Accepted: 02/12/2013] [Indexed: 12/20/2022]
Abstract
In some insect species, two sites of juvenile hormone (JH) synthesis have been reported: the very well documented corpora allata that secrete JH for "general use", and the reproductive system, in particular the male accessory glands, in which the function of the sometimes huge amounts of JH (e.g. in Hyalophora cecropia) remains to be clarified. A recent finding in Schistocerca gregaria, namely that suppression of the ecdysteroid peak preceding a molt by RNAi of the Halloween genes spook, phantom and shade does not impede normal molting, challenges the (never experimentally proven) classical concept that such a peak is causally linked to a molt. Recent developments in epigenetic control of gene expression in both the honey bee and in locusts suggest that, in addition to the classical scheme of hormone-receptor (membrane- and/or nuclear) mode of action, there may be a third way. Upon combining these and other orphan data that do not fit in the commonly accepted textbook schemes, we here advance the working hypothesis that both JH and ecdysone might be important but overlooked players in epigenetic control of gene expression, in particular at extreme concentrations (peak values or total absence). In this review, we put forward how epi-endocrinology can complement classical arthropod endocrinology.
Collapse
Affiliation(s)
- Arnold De Loof
- Research Group of Functional Genomics and Proteomics, KU Leuven, Naamsestraat 59, Bus 2465, 3000 Leuven, Belgium.
| | | | | | | |
Collapse
|
5
|
Loeb MJ, Woods CW, Brandt EP, Boakovec AB. Larval testes of the tobacco budworm: a new source of insect ecdysteroids. Science 2010; 218:896-8. [PMID: 17807143 DOI: 10.1126/science.218.4575.896] [Citation(s) in RCA: 84] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
Testes of last-instar larvae of the tobacco budworm release five times more ecdysteroid into incubation medium (judged by radioimmunoassay) in 2.5 hours than is found in testis homogenates. Incubation of testicular components indicates that the testis sheath may be the site of ecdysteroid synthesis. Fractionation of hemalymph, testis homogenate, and incubation medium by high-performance liquid chromatography produces a distinct ecdysteroid pattern in each case. Thus, released testis ecdysteroids are probably converted to other forms for use, sequestration, or general circulation. Their functions are unknown.
Collapse
|
6
|
Crema R, Bergamini I. On the control of a sexual character in the aphidAcyrthosiphon pisum: the sex pheromone glands of oviparous females. ACTA ACUST UNITED AC 2009. [DOI: 10.1080/11250008509440540] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
|
7
|
Brown MR, Sieglaff DH, Rees HH. Gonadal ecdysteroidogenesis in arthropoda: occurrence and regulation. ANNUAL REVIEW OF ENTOMOLOGY 2009; 54:105-25. [PMID: 18680437 PMCID: PMC7205109 DOI: 10.1146/annurev.ento.53.103106.093334] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
Ecdysteroids are multifunctional hormones in male and female arthropods and are stored in oocytes for use during embryogenesis. Ecdysteroid biosynthesis and its hormonal regulation are demonstrated for insect gonads, but not for the gonads of other arthropods. The Y-organ in the cephalothorax of crustaceans and the integument of ticks are sources of secreted ecdysteroids in adults, as in earlier stages, but the tissue source is not known for adults in many arthropod groups. Ecdysteroid metabolism occurs in several tissues of adult arthropods. This review summarizes the evidence for ecdysteroid biosynthesis by gonads and its metabolism in adult arthropods and considers the apparent uniqueness of ecdysteroid hormones in arthropods, given the predominance of vertebrate-type steroids in sister invertebrate groups and vertebrates.
Collapse
Affiliation(s)
- Mark R Brown
- Department of Entomology, University of Georgia, Athens, Georgia 30602, USA.
| | | | | |
Collapse
|
8
|
Hägele BF, Wang FH, Sehnal F, Simpson SJ. Effects of crowding, isolation, and transfer from isolation to crowding on total ecdysteroid content of eggs in Schistocerca gregaria. JOURNAL OF INSECT PHYSIOLOGY 2004; 50:621-628. [PMID: 15234622 DOI: 10.1016/j.jinsphys.2004.04.008] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/08/2004] [Revised: 04/08/2004] [Accepted: 04/14/2004] [Indexed: 05/24/2023]
Abstract
We examined the ecdysteroid content of eggs from crowd-reared and solitary-reared desert locusts, Schistocerca gregaria, throughout embryogenesis from the day of egg laying until shortly before hatching on day 14. Depending on the time during incubation, ecdysteroid content in eggs from crowd-reared females was 5-10 times higher than in eggs from solitary-reared females. Our investigation revealed two peaks in ecdysteroid content of eggs from crowd-reared females, a small one at day 3 and a major peak at day 10 of incubation. At days 10, 12 and 14 during incubation of eggs from crowd-reared females, we found a positive correlation between egg mass and ecdysteroid content. There was no difference between eggs from the bottom and the top of individual egg pods, but variation in ecdysteroid content between egg pods from different females was considerable in all treatment groups. A brief crowding of solitary-reared females at the time of egg laying, a treatment that initiates maternally mediated gregarization of the developing offspring, had no effect on the consistently low ecdysteroid content in the eggs. This result rules out the possibility that the crowding experience of females is transmitted to the offspring by variation in the total amount of ecdysteroids in their eggs.
Collapse
Affiliation(s)
- Bernd F Hägele
- Department of Zoology and University Museum of Natural History, University of Oxford, UK
| | | | | | | |
Collapse
|
9
|
Tawfik AI, Tanaka Y, Tanaka S. Possible involvement of ecdysteroids in embryonic diapause of Locusta migratoria. JOURNAL OF INSECT PHYSIOLOGY 2002; 48:743-749. [PMID: 12770069 DOI: 10.1016/s0022-1910(02)00099-9] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
In the Ibaraki population (Japan) of Locusta migratoria, adult locusts produce diapause eggs under short-day (SD) conditions and non-diapause eggs under long-day (LD) conditions. The identity and titre of ecdysteroids in the ovaries and eggs from LD and SD adult females were investigated by RIA/HPLC. Maternal ecdysteroids accumulated in the developing ovaries represented about 90% polar conjugates, 5% free ecdysteroids and 5% non-hydrolyzable metabolites. Before oviposition the quantity of ecdysteroids reached 29.8+/-1.85 ng 20-hydroxyecdysone equiv. per mg tissue ovaries from LD females and 13.1+/-3.55 ng 20E equiv./mg in ovaries from SD females. The sum of RIA-positive materials in newly laid eggs was more than three times higher in non-diapause eggs than in diapause eggs. Ecdysteroids present in egg extracts comprised about 85% polar conjugates, 5% free ecdysteroids and 10% non-hydrolyzable metabolites. On the other hand, after diapause termination the amount of ecdysteroids increased drastically. Also, the composition of ecdysteroids differed from that observed during diapause and became comparable to that of non-diapause eggs. The significant differences in the ecdysteroids between non-diapause and diapause eggs may suggest the possible involvement of these compounds in the control of embryonic diapause of this locust.
Collapse
Affiliation(s)
- Amer I. Tawfik
- Institute of Insect and Animal Sciences, Ibaraki 305-8634, Tsukuba, Japan
| | | | | |
Collapse
|
10
|
Tawfik AI, Tanaka Y, Tanaka S. Possible involvement of ecdysteroids in photoperiodically induced suppresion of ovarian development in a Japanese strain of the migratory locust, Locusta migratoria. JOURNAL OF INSECT PHYSIOLOGY 2002; 48:411-418. [PMID: 12770090 DOI: 10.1016/s0022-1910(02)00058-6] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
In a Japanese population of Locusta migratoria, adult females become reproductively inactive under crowding and long days (LD) and reproductively active under crowding and short days (SD). The identity and titre of ecdysteroids in the haemolymph and ovaries from adult females reared under SD and LD were investigated by RIA/HPLC. The effects of exogenous juvenile hormone (JH) III treatments on the termination of such reproductive arrest and ecdysteroid contents in LD females were also examined. In general, ecdysteroid titres in both haemolymph and ovaries were significantly higher in reproductively active SD females than in reproductively inactive LD females. A clear difference was also observed in oocyte growth between SD and LD individuals. JH III applications (three consecutive topical applications, 150 &mgr;g per insect per day from day 3) stimulated ovarian development in LD females and significantly increased the haemolymph and ovarian ecdysteroids to a level comparable to that of reproductively active SD adult females.
Collapse
Affiliation(s)
- Amer I. Tawfik
- Institute of Insect and Animal Sciences, Tsukuba, 305-8634, Ibaraki, Japan
| | | | | |
Collapse
|
11
|
Manière G, Vanhems E, Delbecque J. Cyclic AMP-dependent and independent stimulations of ovarian steroidogenesis by brain factors in the blowfly, Phormia regina. Mol Cell Endocrinol 2000; 168:31-40. [PMID: 11064150 DOI: 10.1016/s0303-7207(00)00312-9] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
The involvement of cyclic-AMP (cAMP) as a potential second messenger in the neurohormonal control of ovarian steroidogenesis was investigated in the adult female blowfly Phormia regina. Individual measurements of ovarian cAMP concentrations and of ovarian biosynthesis of ecdysteroids, stimulated after a protein meal, demonstrated that steroidogenesis is preceded by a peak of cAMP in the ovaries. In vitro, ovarian steroidogenesis was stimulated by cell-permeable analogues of cAMP and by forskolin. Crude brain extracts were also able to elicit a rise of cAMP in the ovaries in vitro and the secretion of ecdysteroids into the medium: such extracts were more active before than after the protein meal, suggesting a rapid release of neuroendocrine material after feeding. Extracts were then prepared from the dorso-medial part of the brain, containing the neurosecretory cells of the pars intercerebralis (PI): these extracts were again found to stimulate the ovarian ecdysteroid secretion, but surprisingly, they failed to trigger a rise of cAMP in the ovaries in vitro. However, extracts from the rest of the cephalic nervous mass, deprived of PI, were also steroidogenic and they increased ovarian cAMP. Experiments with Rp-cAMPS, a cAMP antagonist, were not able to prevent the ecdysteroid stimulation by PI extracts, but did so partly for the extracts deprived of PI. This study thus indicates that at least two different cephalic factors are able to stimulate ovarian steroidogenesis in the blowfly, one elaborated by PI and acting via a cAMP-independent mechanism, and the other elaborated outside PI and using cAMP as a second messenger.
Collapse
Affiliation(s)
- G Manière
- Laboratoire de Neuroendocrinologie des Insectes, Université Bordeaux 1, Avenue des Facultés, F-33405 Cedex, Talence, France
| | | | | |
Collapse
|
12
|
Seslija D, Blagojević D, Spasić M, Tucić N. Activity of superoxide dismutase and catalase in the bean weevil (Acanthoscelides obtectus) selected for postponed senescence. Exp Gerontol 1999; 34:185-95. [PMID: 10363786 DOI: 10.1016/s0531-5565(98)00078-3] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Relationship of superoxide dismutase and catalase activities and aging were tested using bean weevil lines selected for postponed senescence. The beetles of different age (young and old) and mating status (virgin and mated) from the extended longevity lines were compared with their counterparts derived from the short-lived lines for activities of SOD and catalase. The old beetles from the long-lived lines had statistically significant higher activity of SOD than their controls. Although we did not find a significant effect of catalase on longevity, beetles originating from both types of lines exhibited an increased catalase activity during mating processes. In addition, we did observe an increased activity of catalase in one-day-old beetles of the short-lived lines relative to the same-aged individuals of the long-lived lines.
Collapse
Affiliation(s)
- D Seslija
- Department of Evolutionary Biology, Institute for Biological Research, Belgrade, Serbia, Yugoslavia
| | | | | | | |
Collapse
|
13
|
|
14
|
Tawfik AI, Vedrova A, Sehnal F. Ecdysteroids during ovarian development and embryogenesis in solitary and gregarious schistocerca gregaria. ARCHIVES OF INSECT BIOCHEMISTRY AND PHYSIOLOGY 1999; 41:134-143. [PMID: 10398336 DOI: 10.1002/(sici)1520-6327(1999)41:3<134::aid-arch4>3.0.co;2-6] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Maternal ecdysteroids identified in the vitellogenic oocytes of Schistocerca gregaria included more than 80% polar conjugates, up to 5% free ecdysteroids, and up to 15% non-hydrolyzable polar metabolites. The representations of ecdysone (E), 20-hydroxyecdysone (20E), and 2-deoxyecdysone (2dE) in the conjugates was about 16:3:1, and in the free ecdysteroids about 3:1:1. The quantity of ecdysteroids in the ovaries before egg-laying reached 2.3 ng 20E equiv. per mg tissue in the solitary, and 8.9 ng/mg in the gregarious females. Newly laid eggs contained 14 ng and 89 ng, respectively, of 20E equiv. per egg. Nearly all egg ecdysteroids were in form of conjugates and their content declined during the first half of embryonic development. The amount of ecdysteroids sharply increased to over 70 ng 20E equiv./egg in the solitary, and to nearly 400 ng/egg in the gregarious phase. In the second half of embryonic development, the representation of conjugates in total ecdysteroids was reduced to 45-55%, whereas that of free E + 20E rose to 30-40%. Free 2dE remained low but, in the gregarious embryos, free 26E increased to 10% of all ecdysteroids. The conjugates of solitary embryos contained nearly exclusively E and 20E (in ratio 2:1), whereas those of the gregarious embryos included E, 20E, 2dE, and 26E (in ratio 12:7:4:1). Towards the end of embryonic development, the amounts of conjugates and of free ecdysteroids decreased, while that of polar metabolites rose. A sharp drop in ecdysteroid content was associated with hatching but the more than five times higher ecdysteroid level in the gregarious than in the solitary phase was maintained in the newly hatched larvae. Arch. Copyright 1999 Wiley-Liss, Inc.
Collapse
Affiliation(s)
- AI Tawfik
- Zoology Department, Assiut University, Assiut, Egypt
| | | | | |
Collapse
|
15
|
Neural Plasticity in the Adult Insect Brain and Its Hormonal Control. ACTA ACUST UNITED AC 1999. [DOI: 10.1016/s0074-7696(08)62147-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register]
|
16
|
Dinan L. Ecdysteroids in Adults and Eggs of the House Cricket, Acheta domesticus (Orthoptera: Gryllidae). Comp Biochem Physiol B Biochem Mol Biol 1997. [DOI: 10.1016/s0305-0491(96)00221-0] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
|
17
|
Whiting P, Sparks S, Dinan L. Endogenous ecdysteroid levels and rates of ecdysone acylation by intact ovaries in vitro in relation to ovarian development in adult female crickets, Acheta domesticus. ARCHIVES OF INSECT BIOCHEMISTRY AND PHYSIOLOGY 1997; 35:279-299. [PMID: 9177133 DOI: 10.1002/(sici)1520-6327(199705)35:3<279::aid-arch3>3.0.co;2-p] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
Ecdysteroid titres have been determined in adult female house crickets (Acheta domesticus) in relation to reproductive maturation. Ecdysteroid levels in newly emerged adult females are low except in the gut and carcass, which probably reflects the remnants of the preecdysial ecdysteroid peak. Ecdysteroid levels in all compartments increase markedly once ovarian weight surpasses 10 mg. Apolar ecdysteroid conjugates (ecdysone 22-fatty acyl esters) predominate in ovarian tissue throughout ovarian maturation, but low levels of free ecdysteroid and polar conjugated ecdysteroids are also present. During this period, two peaks of ecdysteroids (mainly free and apolar conjugated ecdysteroids) are observed in the haemolymph, gut, and carcass compartments. The peaks in the haemolymph occur when the ovarian mass reaches 30 and 100 mg. The gut and carcass may be acting as sinks or sites of metabolism for the hormone released from the ovaries. The rate of ecdysone acylation by ovaries was found to be developmentally regulated, increasing from low levels in the immature ovaries of newly emerged females as the ovaries increase in size. A semiquantitative assay has been developed to identify compounds which inhibit the conversion of [3H]ecdysone into 22-fatty acyl [3H]ecdysone by ovaries in vitro. A number of ecdysteroids possessing a free hydroxyl group as C-22 as well as the side-chain stereochemistry of ecdysone effectively inhibit this conversion, probably by acting as competitive substrates. In the cases of 20-hydroxyecdysone and ponasterone A, it was clearly demonstrated that these compounds are converted to a mixture of C-22 fatty acyl esters. Several other compounds which have been suggested to affect ecdysteroid metabolism/mode of action in other systems were also tested for their effects on the acyltransferase activity of ovaries in vitro.
Collapse
Affiliation(s)
- P Whiting
- Department of Biological Sciences, University of Exeter, Washington Singer Laboratories, Devon, United Kingdom
| | | | | |
Collapse
|
18
|
De Loof A, Vanden J, Janssen I. Hormones and the cytoskeleton of animals and plants. INTERNATIONAL REVIEW OF CYTOLOGY 1996; 166:1-58. [PMID: 8881772 DOI: 10.1016/s0074-7696(08)62505-x] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
It is often overlooked that a cell can exert its specific functions only after it has acquired a specific morphology: function follows form. The cytoskeleton plays an important role in establishing this form, and a variety of hormones can influence it. The cytoskeletal framework has also been shown to function in a variety of cellular processes, such as cell motility (important for behavior), migration (important for the interrelationship between the endocrine and immune systems, e.g., chemotaxis), intracellular transport of particles, mitosis and meiosis, maintenance of cellular morphology, spatial distribution of cell organelles (e.g., nucleus and Golgi system), cellular responses to membrane events (e.g., endocytosis and exocytosis), intracellular communication including conductance of electrical signals, localization of mRNA, protein synthesis, and--more specifically in plants--ordered cell wall deposition, cytoplasmic streaming, and spindle function followed by phragmoplast function. All classes of hormones seem to make use of the cytoskeleton, either during their synthesis, transport, secretion, degradation, or when influencing their target cells. In this review special attention is paid to cytoskeleton-mediated effects of selected hormones related to growth, transepithelial transport, steroidogenesis, thyroid and parathyroid functioning, motility, oocyte maturation, and cell elongation in plants.
Collapse
Affiliation(s)
- A De Loof
- Zoological Institute of the K.U. Leuven, Belgium
| | | | | |
Collapse
|
19
|
GILLOTT CEDRIC, ISMAIL PREETIM. In vitrosynthesis of ecdysteroid by the male accessory reproductive glands, testis and abdominal integument of the adult migratory grasshopper,Melanoplus sanguinipes. INVERTEBR REPROD DEV 1995. [DOI: 10.1080/07924259.1995.9672435] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
|
20
|
Bylemans D, Borovsky D, Hunt DF, Shabanowitz J, Grauwels L, De Loof A. Sequencing and characterization of trypsin modulating oostatic factor (TMOF) from the ovaries of the grey fleshfly, Neobellieria (Sarcophaga) bullata. REGULATORY PEPTIDES 1994; 50:61-72. [PMID: 8159807 DOI: 10.1016/0167-0115(94)90192-9] [Citation(s) in RCA: 75] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Injection of crude extracts of late vitellogenic ovaries into staged females of the grey fleshfly Neobellieria (Sarcophaga) bullata inhibited oocyte development and biosynthesis of trypsin-like enzymes in the gut. Trypsin synthesis in N. bullata is cyclic and is correlated with egg development, which is discontinuous. A trypsin modulating oostatic factor (Neb-TMOF) was purified from 10,000 vitellogenic ovaries and sequenced by mass spectrometry. Neb-TMOF is a hexapeptide (NH2-NPTNLH-COOH). Injection of the hormone at physiological concentrations (10(-9) M), inhibited trypsin-like synthesis by the midgut of liver-fed female flies, and caused a reduction of the vitellogenin concentration in the hemolymph and of oocyte growth. The role of Neb-TMOF in controlling egg development and the physiological similarities with Aedes-TMOF are discussed.
Collapse
Affiliation(s)
- D Bylemans
- Zoological Institute, Katholieke Universiteit Leuven, Belgium
| | | | | | | | | | | |
Collapse
|
21
|
Sites of ecdysteroid biosynthesis in female adults of Gryllus bimaculatus (Ensifera, Gryllidae). J Comp Physiol B 1992. [DOI: 10.1007/bf00301623] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
|
22
|
Goltzené F, Holder F, Charlet M, Meister M, Oka T. Immunocytochemical localization of Bombyx-PTTH-like molecules in neurosecretory cells of the brain of the migratory locust, Locusta migratoria. A comparison with neuroparsin and insulin-related peptide. Cell Tissue Res 1992; 269:133-40. [PMID: 1423475 DOI: 10.1007/bf00384733] [Citation(s) in RCA: 30] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Using a monoclonal antibody directed against a synthetic pentadecapeptide corresponding to the N-terminus of the prothoracicotropic hormone (PTTH) of Bombyx mori, we report the presence of immunoreactive molecules in a large number of median neurosecretory cells of the pars intercerebralis of the migratory locust, Locusta migratoria. These cells correspond to the A1 cell type which we show to contain also neuroparsins, a family of predominant neurohormones of the migratory locust. In contrast, PTTH-like molecules are absent from A2 cells of the pars intercerebralis which contain Locusta insulin-related peptide (LIRP). Developmental studies show the presence of PTTH-related substances in neurosecretory cells of Locusta migratoria from late embryogenesis to adult development, including ageing vitellogenic female adults.
Collapse
Affiliation(s)
- F Goltzené
- Laboratoire de Biologie Générale de l'Université Louis Pasteur, Unité de Recherche Associée au CNRS 672, Endocrinologie et Immunologie des Insectes, Strasbourg, France
| | | | | | | | | |
Collapse
|
23
|
WEIDNER KARIN, CLASZ MARTINA, RIECK HENRY, HOFFMANN KLAUSH. Developmental changes in ecdysteroid biosynthesisin vitroduring adult life and embryogenesis in a cricket,Giyllus bimaculatusde Geer. INVERTEBR REPROD DEV 1992. [DOI: 10.1080/07924259.1992.9672229] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
|
24
|
|
25
|
Barker GC, Mercer JG, Rees HH, Howells RE. The effect of ecdysteroids on the microfilarial production of Brugia pahangi and the control of meiotic reinitiation in the oocytes of Dirofilaria immitis. Parasitol Res 1991; 77:65-71. [PMID: 1994372 DOI: 10.1007/bf00934388] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
The effects of the ecdysteroids ecdysone and 20-hydroxyecdysone on microfilarial release in Brugia pahangi and on meiotic reinitiation in the oocytes of Dirofilaria immitis were studied. Ecdysone was found to stimulate microfilarial release at 2 x 10(-6) M, but this effect was reduced at higher and lower concentrations. 20-Hydroxyecdysone was found to have no such effect. In D. immitis, ecdysone at 10(-5) M was also found to overcome the period of meiotic arrest that occurs during the pachytene stage of prophase 1. This effect was reduced when 10(-6) M ecdysone was used. These results help support the theory that the ecdysteroids play a hormonal role in filarial worms similar to that found in insects.
Collapse
Affiliation(s)
- G C Barker
- Department of Parasitology, Liverpool School of Tropical Medicine, Pembroke Place, UK
| | | | | | | |
Collapse
|
26
|
Kabbouh M, Rees HH. Characterization of the ATP:2-deoxyecdysone 22-phosphotransferase (2-deoxyecdysone 22-kinase) in the follicle cells of Schistocerca gregaria. ACTA ACUST UNITED AC 1991. [DOI: 10.1016/0020-1790(91)90064-l] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
|
27
|
Wilder MN, Okumura T, Aida K, Hanyu I. Ecdysteroid fluctuations during embryogenesis in the giant freshwater prawn, Macrobrachium rosenbergii. Gen Comp Endocrinol 1990; 80:93-100. [PMID: 2272484 DOI: 10.1016/0016-6480(90)90152-c] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Ecdysteroid levels during the embryogenesis of the giant freshwater prawn, Macrobrachium rosenbergii, were determined by radioimmunoassay and high-performance liquid chromatography. Ecdysteroids consisting of significant amounts of 20-hydroxyecdysone and high-polarity products (HPP) and lesser amounts of ecdysone and low-polarity products (LPP) were detected in mature ovaries and newly laid eggs. All ecdysteroid groups decreased gradually during the nauplius phase. With the formation of the compound eye and the appearance of the carapace and other body-like structures, marking morphogenesis to the zoeal stage, embryos showed the beginning of a continuous and dramatic increase in ecdysteroid concentrations sustained until larval hatchout. Ecdysteroid levels at hatchout were above 20-fold greater than ecdysteroid levels in newly laid eggs. More specifically, HPP and 20-hydroxyecdysone increased concomitantly, with a decrease in 20-hydroxyecdysone only at the end of the embryogenic period, while ecdysone and LPP levels remained low or undetectable. It may be postulated that the presence of ecdysteroids in ovaries and eggs represents a reserve of maternal ecdysteroids which are necessary at the commencement of embryonic development; with the differentiation of embryonic tissue capable of ecdysteroid synthesis, ecdysteroids increase rapidly to play a role in later embryonic development.
Collapse
Affiliation(s)
- M N Wilder
- Department of Fisheries, Faculty of Agriculture, University of Tokyo, Japan
| | | | | | | |
Collapse
|
28
|
Lagueux M, Lwoff L, Meister M, Goltzené F, Hoffmann JA. cDNAs from neurosecretory cells of brains of Locusta migratoria (Insecta, Orthoptera) encoding a novel member of the superfamily of insulins. EUROPEAN JOURNAL OF BIOCHEMISTRY 1990; 187:249-54. [PMID: 1688797 DOI: 10.1111/j.1432-1033.1990.tb15302.x] [Citation(s) in RCA: 99] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
From neurohaemal lobes of corpora cardiaca of Locusta migratoria a 5-kDa peptide has been isolated and its sequence established [see the accompanying paper, by Hietter et al. (1990) Eur. J. Biochem. 187, 241-247]. We have designed oligonucleotide probes from the peptide sequence of this molecule and screened a library prepared from mRNA of the neurosecretory cell region of the brain of this insect. Several positive cDNAs were isolated, the combined nucleotide sequences of which predict a large precursor of 145 residues (15770 Da) containing the newly isolated 5-kDa peptide. The peptide is flanked by regions homologous to the A and B chains of the superfamily of insulins. The overall organization of the precursor is as follows: signal peptide/domain homologous to the B chain of insulins/C (connecting)-peptide (corresponding to the newly isolated 5-kDa peptide)/domain homologous to the A chain of insulins. The numbers and relative positions of the cysteines of the Locusta peptide are equivalent to those of the other members of the insulin superfamily and most of the hydrophobic core residues are conserved.
Collapse
Affiliation(s)
- M Lagueux
- Unité Associée au Centre National de la Recherche Scientifique 672, Université Louis Pasteur, Strasbourg, France
| | | | | | | | | |
Collapse
|
29
|
Ecdysone-controlled meiotic reinitiation in oocytes of Locusta migratoria involves a decrease in cAMP levels. ACTA ACUST UNITED AC 1990. [DOI: 10.1016/0020-1790(90)90076-7] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
|
30
|
LANOT RENÉ, CLÉDON PHILIPPE. Ecdysteroids and meiotic reinitiation inPalaemon serratus(Crustacea Decapoda Natantia) and inLocusta migratoria(Insecta orthoptera). A comparative study. INVERTEBR REPROD DEV 1989. [DOI: 10.1080/07924259.1989.9672074] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
|
31
|
LANOT R, ROUSSEL JP, THIEBOLD JJ. Ecdysteroids and meiotic reinitiation in oocytes ofPeriplaneta americana(Dictyoptera) andGryllus bimaculatus(Orthoptera). INVERTEBR REPROD DEV 1989. [DOI: 10.1080/07924259.1989.9672023] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
|
32
|
Lanot R, Thiebold J, Costet-Corio MF, Benveniste P, Hoffmann JA. Further experimental evidence for the involvement of ecdysone in the control of meiotic reinitiation in oocytes of Locusta migratoria (Insecta, Orthoptera). Dev Biol 1988; 126:212-4. [PMID: 3342933 DOI: 10.1016/0012-1606(88)90255-2] [Citation(s) in RCA: 25] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Ecdysone has recently been shown to be able to trigger meiotic reinitiation in vitro in submature oocytes of Locusta. In the present study we have experimentally depressed (by 60-70%) ecdysone biosynthesis in the ovaries of adult females by rearing them on a diet with a modified sterol profile. Mature oocytes from such females fail to undergo normal reinitiation, but when incubated in vitro, can be induced to break their meiotic arrest by the addition of exogenous ecdysone. These results lend further support to the hypothesis that in Locusta, ovarian ecdysone is involved in the control of meiotic reinitiation.
Collapse
Affiliation(s)
- R Lanot
- U.A. CNRS 672, Université Louis Pasteur, Strasbourg, France
| | | | | | | | | |
Collapse
|
33
|
Involvement of ecdysone in the control of meiotic reinitiation in oocytes of Locusta migratoria (Insecta, orthoptera). Dev Biol 1987. [DOI: 10.1016/0012-1606(87)90150-3] [Citation(s) in RCA: 42] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
|
34
|
Crosby T, Evershed RP, Lewis D, Wigglesworth KP, Rees HH. Identification of ecdysone 22-long-chain fatty acyl esters in newly laid eggs of the cattle tick Boophilus microplus. Biochem J 1986; 240:131-8. [PMID: 3030275 PMCID: PMC1147385 DOI: 10.1042/bj2400131] [Citation(s) in RCA: 48] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
The five major apolar ecdysone esters present in newly laid eggs of the cattle tick Boophilus microplus have been purified by h.p.l.c. The quantities of the apolar esters present in the eggs were increased by administration of ecdysone to the mature females. G.c.-m.s. analysis, as their methyl esters, of the fatty acids released from the apolar ecdysone derivatives by alkali, coupled with positive-ion fast-atom-bombardment m.s. of the intact ecdysone esters, showed that the compounds consisted of a series of fatty acyl esters of ecdysone. The position of esterification of the ecdysone was established by p.m.r. spectroscopy. The combined data show that the novel apolar derivatives of ecdysone consist of the 22-palmitate, -palmitoleate, -stearate, -oleate, and -linoleate esters respectively. Confirmation was obtained by comparison with synthetic ecdysone 22-palmitate. The significance of the ecdysone fatty acyl esters as a possible source of free hormone during embryogenesis is discussed.
Collapse
|
35
|
Loeb MJ, Brandt EP, Woods CW. Effects of exogenous ecdysteroid titer on endogenous ecdysteroid production in vitro by testes of the tobacco budworm,Heliothis virescens. ACTA ACUST UNITED AC 1986. [DOI: 10.1002/jez.1402400110] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
|
36
|
Kappler C, Goltzené F, Lagueux M, Hetru C, Hoffmann JA. Role of the follicle cells and the oocytes in ecdysone biosynthesis and esterification in vitellogenic females ofLocusta migratoria. ACTA ACUST UNITED AC 1986. [DOI: 10.1080/01688170.1986.10510177] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
|
37
|
Kappler C, Kabbouh M, Durst F, Hoffmann JA. Studies on the C-2 hydroxylation of 2-deoxyecdysone in Locusta migratoria. ACTA ACUST UNITED AC 1986. [DOI: 10.1016/0020-1790(86)90074-0] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
|
38
|
Dübendorfer A, Maróy P. Ecdysteroid conjugation by tissues of adult females of Drosophila melanogaster. ACTA ACUST UNITED AC 1986. [DOI: 10.1016/0020-1790(86)90084-3] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
|
39
|
|
40
|
Meister MF, Dimarcq JL, Kappler C, Hetru C, Lagueux M, Lanot R, Luu B, Hoffmann JA. Conversion of a radiolabelled ecdysone precursor, 2,22,25-trideoxyecdysone, by embryonic and larval tissues of Locusta migratoria. Mol Cell Endocrinol 1985; 41:27-44. [PMID: 3839194 DOI: 10.1016/0303-7207(85)90140-6] [Citation(s) in RCA: 44] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
A high specific activity tritiated ecdysone precursor, 2,22,25-trideoxyecdysone, was used to probe the capacity of various embryonic and larval tissues to perform the last 3 hydroxylation steps in ecdysone biosynthesis. Embryos at early stages of development, prior to the differentiation of their endocrine glands and embryonic heads, thoraces and abdomens of later stages, were found to have the capacity to hydroxylate the precursor to ecdysone. Larval epidermis and fat body are also able to transform 2,22,25-trideoxyecdysone into ecdysone; Malpighian tubules and midgut hydroxylate the precursor at C-2 but are apparently unable to hydroxylate both at C-22 and C-25. Larval prothoracic glands convert the precursor to ecdysone at a very efficient rate, which is 1-2 magnitudes higher than that of the other tissues investigated; several data argue for the existence of a privileged sequence of hydroxylations, C-25, C-22, C-2, in the larval prothoracic glands.
Collapse
|
41
|
Connat JL, Diehl PA, Gfeller H, Morici M. Ecdysteroids in females and eggs of the Ixodid tickAmblyomma hebraeum. ACTA ACUST UNITED AC 1985. [DOI: 10.1080/01688170.1985.10510132] [Citation(s) in RCA: 26] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
|
42
|
Ikekawa N. Chapter 8 Structures, biosynthesis and function of sterols in invertebrates. ACTA ACUST UNITED AC 1985. [DOI: 10.1016/s0167-7306(08)60684-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/08/2023]
|
43
|
|
44
|
Rees HH, Isaac RE. Biosynthesis and metabolism of ecdysteroids and methods of isolation and identification of the free and conjugated compounds. Methods Enzymol 1985; 111:377-410. [PMID: 3897779 DOI: 10.1016/s0076-6879(85)11024-4] [Citation(s) in RCA: 25] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
|
45
|
Postlethwait JH, Giorgi F. Vitellogenesis in insects. DEVELOPMENTAL BIOLOGY (NEW YORK, N.Y. : 1985) 1985; 1:85-126. [PMID: 3917207 DOI: 10.1007/978-1-4615-6814-8_2] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
|
46
|
Integration in the Insect Endocrine System. ENDOCRINOLOGY II 1985. [DOI: 10.1016/b978-0-08-030809-8.50007-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/02/2023]
|
47
|
Biosynthesis of Ovarian Ecdysteroid Phosphates and Their Metabolic Fate During Embryogenesis in Schistocerca gregaria. ACTA ACUST UNITED AC 1984. [DOI: 10.1007/978-3-642-69922-1_19] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register]
|
48
|
|
49
|
Isaac RE, Rose ME, Rees HH, Goodwin TW. Identification of the 22-phosphate esters of ecdysone, 2-deoxyecdysone, 20-hydroxyecdysone and 2-deoxy-20-hydroxyecdysone from newly laid eggs of the desert locust, Schistocerca gregaria. Biochem J 1983; 213:533-41. [PMID: 6684423 PMCID: PMC1152159 DOI: 10.1042/bj2130533] [Citation(s) in RCA: 29] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
The four major ecdysteroid (insect moulting hormone) conjugates present in the newly laid eggs of the desert locust, Schistocera gregaria, have been purified by reversed-phase and anion-exchange high-performance liquid chromatography. The steroid moieties were identified as ecdysone, 2-deoxyecdysone, 20-hydroxyecdysone and 2-deoxy-20-hydroxyecdysone. Phosphate analysis of acid-hydrolysed samples showed a steroid:phosphate ratio of approx. 1:1 for all four compounds. The intact conjugates were identified as ecdysone 22-phosphate, 2-deoxyecdysone 22-phosphate, 20-hydroxyecdysone 22-phosphate and 2-deoxy-20-hydroxyecdysone 22-phosphate by fast atom bombardment mass spectrometry and 1H, 13C and 31P n.m.r. The significance of ecdysteroid phosphates as a source of free hormone during embryogenesis is discussed.
Collapse
|
50
|
Porcheron P, Papillon M, Baehr JC. Hormonal levels and protein variations during sexual maturation ofSchistocerca gregaria; effect of rearing temperature. ACTA ACUST UNITED AC 1982. [DOI: 10.1007/bf01953683] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
|