A Radioimmunoassay for Arthropod Moulting Hormones, Introducing a Novel Method of Immunogen Coupling

Spindler, Klaus-Dieter; Beckers, C.; Gröschel‐Stewart, Ute; Emmerich, Hans

doi:10.1515/bchm2.1978.359.2.1269

Cited by 55 publications

(7 citation statements)

References 4 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Freshly dissected rat livers were washed and cut into small pieces in icecold phosphate-buffer (22 mM KH2P04/Na2HP04, pH 7.5, 100 mM NaCI, 6 mM KC1, 20 mM glucose, and 5 mM EDTA). The liver was homogenized in 20 mM Tris-HC1 buffer (pH 7.4) containing 20% glycerol, 50 mM KC1,2.5 mM EDTA, 5 mM pmercaptoethanol, and the protease inhibitors mentioned above by 10 strokes in a Dounce all-glass homogenizer. The supernatant from a lowspeed centrifugation (lO,OOOg, 4"C, 20 min) was recentrifuged at 100,OOOg (1 h, 4°C); the final (100,OOOg) supernatant was used for binding studies.…”

Section: Steroid Receptor Binding Assaysmentioning

confidence: 99%

On the action of RH 5849, a nonsteroidal ecdysteroid agonist, on a cell line from Chironomus tentans

Spindler-Barth

Turberg

Spindler

1991

Arch Insect Biochem Physiol

Self Cite

View full text Add to dashboard Cite

RH 5849 competes with 3H-ponasterone A for ecdysteroid binding sites in Chironomus tentans cells with an about fourfold lower relative affinity as compared to 20-OH-ecydsone. It does not interfere with glucocorticoid and estrogen binding sites in vertebrates. It i s also not recognized by an ecdysteroid antibody. RH 5849 exerts typical morphological and physiological effects ascribed to the action of 20-OH-ecdysone o n C. tentans cells, namely an increase in acetylcholinesterase activity and an inhibition of chitin synthesis.

show abstract

Section: Steroid Receptor Binding Assaysmentioning

confidence: 99%

On the action of RH 5849, a nonsteroidal ecdysteroid agonist, on a cell line from Chironomus tentans

Spindler-Barth

Turberg

Spindler

1991

Arch Insect Biochem Physiol

Self Cite

View full text Add to dashboard Cite

show abstract

“…The insects were extracted in methanol water (7:3) to determine the ecdysteroid concentrations. Extraction of ecdysteroids as well as radioirnmunoassay were performed essentially as described previously [3], using antiserum ICT-1 [9]. To effectively extract the eggs, glass-glass homogenizers were used.…”

Section: Extraction Of Ecdysteroids and Radioimmunoassaymentioning

confidence: 99%

Effect of a juvenile hormone analogue on the life span, egg laying, and ecdysteroid titer of virgin Ephestia cautella females

Shaaya

Calderon

Pisarev

et al. 1991

Arch Insect Biochem Physiol

Self Cite

View full text Add to dashboard Cite

Mated females of the tropical warehouse moth, Ephestia cautella, start laying eggs shortly after adult emergence. All eggs are laid within 4 days and the adult's total life span is 5 to 6 days. If mating i s prevented, egg laying is drastically delayed and the life span is extended to approximately 10 to 11 days. Virgin females lay fewer eggs than mated insects. If the juvenile hormone analogue methoprene is applied topically (100 ng/pupa) 2 to 3 days prior to adult emergence, the number of eggs per virgin female increases and the life span is reduced, as compared with nontreated virgins, and reaches values similar to control (mated) females. Changes in the ecdysteroid titer of females are related to egg laying. The concentrations increase and reach a maximum before most of the eggs are laid. Accordingly, the peak maximum is delayed in virgins as compared with mated females. This delay i s prevented after application of methoprene. Mated and virgin females have lower ecdysteroid levels than treated virgins. In contrast to mated females, males have much lower ecdysteroid levels throughout their adult life.

show abstract

“…Four different antisera were used for dose-response studies with samples of LP1 and LP2, purified by two successive reversed-phase HPLC separations. Both the Horn 12 [16 wk; a batch related to the H21B antiserum (11)] and the ICT-1 antisera are ecdysone nucleus specific (16): the ecdysteroids used in their preparation were conjugated to the carrier via the ecdysteroid side chain (12,16). Conversely, the DHS 1-15 antiserum, prepared by conjugating through C2 on the steroid nucleus, is relatively side chain specific (13).…”

Section: Hplc Separation Of Ecdysteroids Secreted By Drosophilamentioning

confidence: 99%

Evidence for the presence of makisterone A in Drosophila larvae and the secretion of 20-deoxymakisterone A by the ring gland

Redfern

1984

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

View full text Add to dashboard Cite

Ring glands or brain-ring gland complexes from third-instar Drosophila melanogaster larvae secreted ecdysone [(22R)-2j3,3,,14a,22,25-pentahydroxy-5i3-cholest-7-en-6-oneJ and two less polar ecdysteroids (LP1 and LP2) in vitro. Radioimmunoassay with different antisera indicated that LP1 and LP2 are side-chain-modified analogues of ecdysone. In high-performance liquid chromatography, the retention time of LP2 was equivalent to that of a precursor of makisterone A [(20R,22R)-2fi,3fi,l4a,20,22,25-hexahydroxy-24-methyl-5p-cholest-7-en-6-one] secreted by Dysdercusfasciatus prothoracic glands in vitro. LP2 was metabolized in vitro by the fat body of DrosophilM larvae to a product with the characteristics of iakisterone A when analyzed by gas chromatography/mass spectrometry (selected ion nionitoring). Evidence was obtained for the presence of mikisterone A in. Drosophila larvae. These data suggest that LP2 is 20-deoxymakisterone A (24-methylecdysone) and that makisterone A could function as an additional moulting hormone in Drosophila, although 20-deoxymakisterone A production is apparently dependent on the sterol composition of the diet. LP1 has not been identified.The insect steroid ecdysone, a C27 ecdysteroid [(22R)-2p,3,8 14a,22,25-pentahydroxy-5p-cholest-7-en-6-one], is secreted by the prothoracic glands (1) or, in cyclorrhaphous Diptera, by the ring gland (2). Ecdysone is hydroxylated at C-20 by monooxygenase enzyme systems in the fat body, gut, and Malpighian tubules to give the biologically active moulting hormone 20-hydroxyecdysone [(20R,22R)-2P,3,8,14a,20,22,25-hexahydroxy-5/3-cholest-7-en-6-oneI (3).Recently, the moulting hormone in Dysdercus fasciatus (4) and some other species of phytophagous Hemiptera (5) has been identified as a C28 ecdysteroid, makisterone A [(20R,22R)-2(,3(3,14a,20,22,25-hexahydroxy-24-methyl-5f3-cholest-7-en-6-one], which differs from 20-hydroxyecdysone in the presence of an additional methyl group at C-24 of the ecdysteroid side chain. By analogy with other insects (1), the prothoracic glands of these hemipterans would be expected to secrete the 24-methylated analogue of ecdysone, 20-deoxymakisterotle A (24-methylecdysone).In a previous study, it was shown that Drosophila ring glands secrete ecdysteroids in vitro and that the rate of secretion rea'ches a maximum towards the end of the last larval instar (6). Sarcophaga ring glands secrete ecdysone in vitro (2), and the experiments reported here were initially designed (7) were used.Yeast RNA was replaced with uridine and inosine, and lecithin was replaced with choline chloride (7). The medium constituents were purchased from Sigma [uridine, nicotinic acid, thiamine HCl, calcium pantothenate, pyridoxine, biotin, and ergosterol (ergosta-5,7,22E-trien-3,8-ol) Organ Culture. Ring glands or brain-ring gland complexes from third-instar Drosophila larvae with partially or fully bloated larval salivary glands were dissected and cultured (three to six ring glands or brain-ring gland complexes per culture) in Grace's medium (Flow La...

show abstract

A Radioimmunoassay for Arthropod Moulting Hormones, Introducing a Novel Method of Immunogen Coupling

Cited by 55 publications

References 4 publications

On the action of RH 5849, a nonsteroidal ecdysteroid agonist, on a cell line from Chironomus tentans

On the action of RH 5849, a nonsteroidal ecdysteroid agonist, on a cell line from Chironomus tentans

Effect of a juvenile hormone analogue on the life span, egg laying, and ecdysteroid titer of virgin Ephestia cautella females

Evidence for the presence of makisterone A in Drosophila larvae and the secretion of 20-deoxymakisterone A by the ring gland

Contact Info

Product

Resources

About