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Weiner AC, Chen HY, Roegner ME, Watson RD. Calcium signaling and regulation of ecdysteroidogenesis in crustacean Y-organs. Gen Comp Endocrinol 2021; 314:113901. [PMID: 34530000 DOI: 10.1016/j.ygcen.2021.113901] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/27/2021] [Revised: 09/06/2021] [Accepted: 09/09/2021] [Indexed: 01/21/2023]
Abstract
Crustacean Y-organs secrete ecdysteroid molting hormones. Ecdysteroids are released in increased amount during premolt, circulate in hemolymph, and stimulate the events in target cells that lead to molting. During much of the molting cycle, ecdysteroid production is suppressed by molt-inhibiting hormone (MIH), a peptide neurohormone produced in the eyestalks. The suppressive effect of MIH is mediated by a cyclic nucleotide second messenger. A decrease in circulating MIH is associated with an increase in the hemolymphatic ecdysteroid titer during pre-molt. Nevertheless, it has long been hypothesized that a positive regulatory signal or stimulus is also involved in promoting ecdysteroidogenensis during premolt. Data reviewed here are consistent with the hypothesis that an intracellular Ca2+ signal provides that stimulus. Pharmacological agents that increase intracellular Ca2+ in Y-organs promote ecdysteroidogenesis, while agents that lower intracellular Ca2+ or disrupt Ca2+ signaling suppress ecdysteroidogenesis. Further, an increase in the hemolymphatic ecdysteroid titer after eyestalk ablation or during natural premolt is associated with an increase in intracellular free Ca2+ in Y-organ cells. Several lines of evidence suggest elevated intracellular calcium is linked to enhanced ecdysteroidogenesis through activation of Ca2+/calmodulin dependent cyclic nucleotide phosphodiesterase, thereby lowering intracellular cyclic nucleotide second messenger levels and promoting ecdysteroidogenesis. Results of transcriptomic studies show genes involved in Ca2+ signaling are well represented in Y-organs. Several recent studies have focused on Ca2+ transport proteins in Y-organs. Complementary DNAs encoding a plasma membrane Ca2+ ATPase (PMCA) and a sarcoplasmic/endoplasmic reticulum Ca2+ ATPase (SERCA) have been cloned from crab Y-organs. The relative abundance of PMCA and SERCA transcripts in Y-organs is elevated during premolt, a time when Ca2+ levels in Y-organs are likewise elevated. The results are consistent with the notion that these transport proteins act to maintain the Ca2+ gradient across the cell membrane and re-set the cell for future Ca2+ signals.
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Affiliation(s)
- Amanda C Weiner
- Department of Biology, University of Alabama at Birmingham, Birmingham, AL 35294, United States
| | - Hsiang-Yin Chen
- Department of Biology, University of Alabama at Birmingham, Birmingham, AL 35294, United States
| | - Megan E Roegner
- Department of Biology, University of Alabama at Birmingham, Birmingham, AL 35294, United States
| | - R Douglas Watson
- Department of Biology, University of Alabama at Birmingham, Birmingham, AL 35294, United States.
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Swall ME, Benrabaa SAM, Tran NM, Tran TD, Ventura T, Mykles DL. Characterization of Shed genes encoding ecdysone 20-monooxygenase (CYP314A1) in the Y-organ of the blackback land crab, Gecarcinus lateralis. Gen Comp Endocrinol 2021; 301:113658. [PMID: 33159911 DOI: 10.1016/j.ygcen.2020.113658] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/04/2020] [Revised: 10/28/2020] [Accepted: 10/31/2020] [Indexed: 11/23/2022]
Abstract
Molting in decapod crustaceans is controlled by ecdysteroid hormones synthesized and secreted by the molting gland, or Y-organ (YO). Halloween genes encode cytochrome P450 enzymes in the ecdysteroid synthetic pathway. The current paradigm is that YOs secrete an inactive precursor (e.g., ecdysone or E), which is hydroxylated at the #20 carbon to form an active hormone (20-hydroxyecdysone or 20E) by a mitochonrial 20-monooxygenase (CYP314A1) in peripheral tissues. 20-Monooxygenase is encoded by Shed in decapods and Shade in insects. We used eastern spiny lobster Shed sequences to extract six orthologs in the G. lateralis YO transcriptome. Phylogenetic analysis of the deduced amino acid sequences from six decapod species organized the Sheds into seven classes (Sheds 1-7), resulting in the assignment of the G. lateralis Sheds to Gl-Shed1, 2, 4A, 4B, 5A, and 5B. The mRNA levels of the six Gl-Sheds in the YO of intermolt animals were comparable to those in nine other tissues that included hepatopancreas and muscle. qPCR was used to compare the effects of molt induction by multiple leg autotomy (MLA) and eyestalk ablation (ESA) on Gl-Shed mRNA levels in the YO. Molt stage had little effect on Gl-Shed1 and Gl-Shed5B expression in the YO of MLA animals. Gl-Shed5A was expressed at the highest mRNA levels in the YO and was significantly increased during early and mid premolt stages. By contrast, ESA ± SB431542 had no effect on Gl-Shed expression at 1, 3, 5, and 7 days post-ESA. SB431542, which inhibits Transforming Growth Factor-β/activin signaling and blocks YO commitment, decreased Gl-Shed2 and Gl-Shed4A mRNA levels at 14 days post-ESA. A targeted metabolomic analysis showed that YOs cultured in vitro secreted E and 20E to the medium. These data suggest that the YO expresses 20-monooygenases that can convert E to 20E, which may contribute to the increase in active hormone in the hemolymph during premolt.
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Affiliation(s)
- Madeleine E Swall
- Department of Biology, Colorado State University, Fort Collins, CO 80523, USA
| | - Samiha A M Benrabaa
- Department of Biology, Colorado State University, Fort Collins, CO 80523, USA
| | - Nhut M Tran
- GeneCology Research Centre, School of Science and Engineering, University of the Sunshine Coast, Queensland 4556, Australia
| | - Trong D Tran
- GeneCology Research Centre, School of Science and Engineering, University of the Sunshine Coast, Queensland 4556, Australia
| | - Tomer Ventura
- GeneCology Research Centre, School of Science and Engineering, University of the Sunshine Coast, Queensland 4556, Australia
| | - Donald L Mykles
- Department of Biology, Colorado State University, Fort Collins, CO 80523, USA.
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Roegner ME, Watson RD. De novo transcriptome assembly and functional annotation for Y-organs of the blue crab (Callinectes sapidus), and analysis of differentially expressed genes during pre-molt. Gen Comp Endocrinol 2020; 298:113567. [PMID: 32710897 DOI: 10.1016/j.ygcen.2020.113567] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/13/2020] [Revised: 07/14/2020] [Accepted: 07/19/2020] [Indexed: 12/11/2022]
Abstract
Blue crabs (Callinectes sapidus) undergo incremental growth involving the shedding (molting) of the old exoskeleton, and subsequent expansion and re-calcification of the newly synthesized one. The cellular events that lead to molting are triggered by steroid hormones termed ecdysteroids released from Y-organs, paired endocrine glands located in the anterior cephalothorax. The regulatory pathways leading to increased synthesis and release of ecdysteroids are not fully understood, and no transcriptome has yet been published for blue crab Y-organs. Here we report de novo transcriptome assembly and annotation for adult blue crab Y-organs, and differential gene expression (DGE) analysis between Y-organs of intermolt and premolt crabs. After trimming and quality assessment, a total of 91,819,458 reads from four cDNA libraries were assembled using Trinity to form the reference transcriptome. Trinity produced a total of 171,530 contigs coding for 150,388 predicted genes with an average contig length of 613 and an N50 of 940. Of these, TransDecoder predicted 31,661 open reading frames (ORFs), and 10,210 produced non-redundant blastx results through Trinotate annotation. Genes involved in multiple cell signaling pathways, including Ca2+ signaling, cGMP signaling, cAMP signaling, and mTOR signaling were present in the annotated reference transcriptome. DGE analysis showed in premolt Y-organs up-regulated genes involved in energy production, cholesterol metabolism, and exocytosis. The results provide insights into the transcriptome of blue crab Y-organs during a natural (rather than experimentally induced) molting cycle, and constitute a step forward in understanding the cellular mechanisms that underlie stage-specific changes in the synthesis and secretion of ecdysteroids by Y-organs.
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Affiliation(s)
- Megan E Roegner
- Department of Biology, University of Alabama at Birmingham, Birmingham, AL 35294, United States
| | - R Douglas Watson
- Department of Biology, University of Alabama at Birmingham, Birmingham, AL 35294, United States.
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Roegner ME, Roer RD, Watson RD. Sarco/endoplasmic reticulum Ca2+ ATPase (SERCA) transcript abundance in Y-organs and ecdysteroid titer in hemolymph during a molting cycle of the Blue Crab, Callinectes sapidus. Comp Biochem Physiol A Mol Integr Physiol 2019; 229:76-80. [DOI: 10.1016/j.cbpa.2018.12.006] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2018] [Revised: 12/07/2018] [Accepted: 12/09/2018] [Indexed: 11/25/2022]
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Roegner ME, Chen HY, Watson RD. Molecular cloning and characterization of a sarco/endoplasmic reticulum Ca 2+ ATPase (SERCA) from Y-organs of the blue crab (Callinectes sapidus). Gene 2018; 673:12-21. [PMID: 29886036 DOI: 10.1016/j.gene.2018.06.018] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2018] [Revised: 05/28/2018] [Accepted: 06/06/2018] [Indexed: 11/27/2022]
Abstract
Existing data indicate that a Ca2+ signal stimulates ecdysteroid hormone production by crustacean molting glands (Y-organs). Ca2+ signaling is dependent on a tightly regulated Ca2+ gradient, with intracellular free Ca2+ maintained at a low basal level (typically sub-micromolar). This is achieved through the action of proteins intrinsic to the plasma membrane and the membranes of organelles. One such protein, the sarco/endoplasmic reticulum Ca2+ ATPase (SERCA), pumps Ca2+ from cytosol to the lumen of the endoplasmic reticulum. As a step toward understanding Ca2+-mediated regulation of ecdysteroidogenesis, we have begun investigating Ca2+ transport proteins in Y-organs. In studies reported here, we used a PCR-based strategy to clone from Y-organs of the blue crab (Callinectes sapidus) a cDNA encoding a putative SERCA protein. The cloned Cas-SERCA cDNA (3806 bp) includes a 3057-bp open reading frame that encodes a 1019-residue protein (Cas-SERCA). The conceptually translated protein has a predicted molecular mass of 111.42 × 103 and contains all signature domains of an authentic SERCA, including ten transmembrane domains and a phosphorylation site at aspartate 351. A homology model of Cas-SERCA closely resembles models of related SERCA proteins. Phylogenetic analysis shows Cas-SERCA clusters with SERCA proteins from other arthropods. An assessment of tissue distribution indicates the Cas-SERCA transcript is widely distributed across tissues. Studies using quantitative PCR showed Cas-SERCA transcript abundance increased significantly in Y-organs activated by eyestalk ablation, a pattern consistent with the hypothesis that Cas-SERCA functions to maintain Ca2+ homeostasis in Y-organs.
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Affiliation(s)
- Megan E Roegner
- Department of Biology, University of Alabama at Birmingham, Birmingham, AL 35294, United States
| | - Hsiang-Yin Chen
- Department of Biology, University of Alabama at Birmingham, Birmingham, AL 35294, United States
| | - R Douglas Watson
- Department of Biology, University of Alabama at Birmingham, Birmingham, AL 35294, United States.
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Chen HY, Dillaman RM, Roer RD, Watson RD. Stage-specific changes in calcium concentration in crustacean (Callinectes sapidus) Y-organs during a natural molting cycle, and their relation to the hemolymphatic ecdysteroid titer. Comp Biochem Physiol A Mol Integr Physiol 2012; 163:170-3. [DOI: 10.1016/j.cbpa.2012.05.205] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2012] [Revised: 05/30/2012] [Accepted: 05/30/2012] [Indexed: 10/28/2022]
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Mykles DL. Ecdysteroid metabolism in crustaceans. J Steroid Biochem Mol Biol 2011; 127:196-203. [PMID: 20837145 DOI: 10.1016/j.jsbmb.2010.09.001] [Citation(s) in RCA: 100] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/27/2010] [Revised: 09/01/2010] [Accepted: 09/02/2010] [Indexed: 01/30/2023]
Abstract
The molting gland, or Y-organ (YO), is the primary site for ecdysteroid synthesis in decapod crustaceans. Ecdysteroid biosynthesis is divided into two stages: (1) conversion of cholesterol to 5β-diketol and (2) conversion of 5β-diketol to secreted products. Stage 1 involves the conversion of cholesterol to 7-dehydrocholesterol (7DC) by 7,8-dehydrogenase, the "Black Box" reactions involving 3-oxo-Δ(4) intermediates, and the conversion of Δ(4)-diketol to 5β-diketol by 5β[H]-reductase. The stage 2 reactions generate four major products, depending on species: ecdysone, 3-dehydroecdysone (3DE), 25-deoxyecdysone (25dE), and 3-dehydro-25-deoxyecdysone (3D25dE). Peripheral tissues convert these compounds to the active hormones 20-hydroxyecdysone (20E) and ponasterone A (25-deoxy-20-hydroxyecdysone or 25d20E). The hydroxylations at C25, C22, C2, and C20 are catalyzed by cytochrome P-450 mono-oxygenases, which are encoded by the Halloween genes Phantom, Disembodied, Shadow, and Shade, respectively, in insects. Orthologs of these genes are present in the Daphnia genome and a cDNA encoding Phantom has been cloned from prawn. Inactivation involves conversion of ecdysteroids to polar metabolites and/or conjugates, which are eliminated in the urine and feces. The antennal gland is the major route for excretion of ecdysteroids synthesized by the YO. The hepatopancreas eliminates ingested ecdysteroids by forming apolar conjugates. The concentrations of ecdysteroids vary over the molt cycle and are determined by the combined effects biosynthesis, metabolism, and excretion.
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Affiliation(s)
- Donald L Mykles
- Department of Biology, Colorado State University, Campus 1878, Fort Collins, CO 80523, USA.
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Chen HY, Watson RD. Changes in intracellular calcium concentration in crustacean (Callinectes sapidus) Y-organs: relation to the hemolymphatic ecdysteroid titer. ACTA ACUST UNITED AC 2010; 315:56-60. [DOI: 10.1002/jez.646] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Wang WL, Spaziani E, Huang ZH, Charkowski DM, Li Y, Liu XM. Ecdysteroid hormones and metabolites of the stone crab, Menippe mercenaria. THE JOURNAL OF EXPERIMENTAL ZOOLOGY 2000; 286:725-35. [PMID: 10797325 DOI: 10.1002/(sici)1097-010x(20000601)286:7<725::aid-jez7>3.0.co;2-n] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
The Y-organs of the xanthid crab Menippe mercenaria secrete the ecdysteroids, 3-dehydroecdysone (3DE) and lesser amounts of 3-dehydro (or 2-dehydro)-25-deoxyecdysone (3D25dE) in vitro. These ecdysteroids were identified by elution-time comparisons with authentic standards, mass spectrography, and, for 3D25dE, infrared spectrometry. Tissues were incubated 18 hr with [(3)H]3DE. Activities representing 3beta-reductase and 20-hydroxylase generally were present, evidenced by finding in the tissue/medium extract labeled ecdysone (E) and 20-hydroxyecdysone (20E). Labeled 3-dehydro-20-hydroxyecdysone (3D20E) also appeared to be present. Tissue blanks and hemolymph were devoid of activity. Muscle was low, hypodermis was intermediate, and hindgut and gonads were high in activity of the enzymes. Consistent with the presence of these enzymes in peripheral tissues, ecdysteroid products identified in the hemolymph were 20E, 3D20E, and 25-deoxy-20-hydroxyecdysone (25d20E; ponasterone A). Structures of 20E and 3D20E were confirmed by co-elution with authentic standards in high-performance liquid chromatography (HPLC), co-elution of derivatives in gas chromatography, and mass spectroscopy. Ponasterone A (identified by HPLC co-elution with the standard), like 20E is present in the hemolymph in prominent amounts. These data indicate that Menippe, among crustaceans thus far studied, secretes a unique combination of ecdysteroid hormones, namely, a 3- (or 2-) oxo compound and a 25-deoxy compound. This represents a different kind of branch point from 5beta-diketol in ecdysteroid biosynthesis, in which the intermediate, 5beta-ketodiol is bypassed. A result is the joint appearance in the circulation of the hormones, 20E and ponasterone A, which in other species are singly prominent.
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Affiliation(s)
- W L Wang
- Department of Biological Sciences, University of Iowa, Iowa City, Iowa 52242, USA
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Naya Y, Ohnishi M, Ikeda M, Miki W, Nakanishi K. Physiological role of 3-hydroxykynurenine and xanthurenic acid upon crustacean molting. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 1991; 294:309-18. [PMID: 1772071 DOI: 10.1007/978-1-4684-5952-4_28] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Studies with crabs (Charybdis japonica) and crayfish (Procambarus clarkii) revealed that the tryptophan metabolites, 3-hydroxy-L-kynurenine (3-OH-K) and xanthurenic acid (XA), common secretory products of the X-organ-sinus gland complex of eyestalks from several decapods, regulated the molting of crustaceans in species-nonspecific fashion. Injection of 3-OH-K to the eyestalk-ablated crayfish delayed the onset of the first molt and lengthened the interval between the first and second molts. These lines of evidence were in accord with previous accounts of the so-called "molt inhibiting hormone" (MIH) effect. Removal of eyestalks caused a change in the conversion capacity of exogenous 3-OH-K to XA in the hemolymph. The peak in transformation capacity was followed by a peak in the titer of 20-hydroxyecdysone or molting hormone. Moreover, the seasonal profiles of the XA and ecdysone titers in Charybdis japonica exhibited a staggered relationship in the tissues tested. The ratio of XA to 3-OH-K, which is expected to indicate the apparent 3-OH-Kase activity, fluctuated seasonally and locally. When the Y-organ with the adhering tissues (Y-organ complex or YOC) was incubated during the period of high XA titer, the YOC produced 100 times more ecdysone than before incubation. It is suggested that ecdysteroidogenesis in situ was suppressed during this period by XA, but incubation of the YOC lead to a dramatic acceleration in ecdysone synthesis by overriding this inhibitory effect. XA profoundly repressed ecdysteroidogenesis in the YOC culture. Thus, XA is the ecdysone biosynthesis inhibitor (EBI) and 3-OH-K the precursor in crustaceans. An interfering effect of XA to a biocatalyst cytochrome P-450 system was postulated for the inhibition mechanism of ecdysteroidogenesis.
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Affiliation(s)
- Y Naya
- Suntory Institute for Bioorganic Research, Osaka, Japan
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Molting and growth of eyestalk-ablated juvenile red king crabs, paralithodes camtschatica (crustacea: lithodidae). ACTA ACUST UNITED AC 1988. [DOI: 10.1016/0300-9629(88)90412-4] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Jackson SA, Bruce MJ, Chang ES, Clegg JS. Effects of eyestalk ablation upon water relations in the American lobster,Homarus americanus. ACTA ACUST UNITED AC 1987. [DOI: 10.1002/jez.1402440306] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Watson RD, Spaziani E. Biosynthesis of ecdysteroids from cholesterol by crab Y-organs, and eyestalk suppression of cholesterol uptake and secretory activity, in vitro. Gen Comp Endocrinol 1985; 59:140-8. [PMID: 4018549 DOI: 10.1016/0016-6480(85)90428-9] [Citation(s) in RCA: 64] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Precursor incorporation studies were conducted in vitro with activated Y-organs from 48-hr de-eyestalked Cancer antennarius donors. When the glands were prelabeled in vivo by systemic injection of [3H]cholesterol 12 hr prior to removal, and subsequently incubated 24 hr in label-free medium, the glands secreted 3H-labeled ecdysone. The glands also secreted an unidentified ecdysteroid with comigrating 3H-label with characteristic retention time on normal-phase HPLC of 4 min (4-min unknown). The compound is less polar, and is secreted in a quantity and apparent specific activity approximately fivefold greater, than ecdysone. Compared with chromatographic retention times and competitive binding curves of authentic standards, the 4-min unknown was determined not to be ponasterone A, inokosterone, makisterone, or several other possible products or intermediates. In contrast with Y-organs from intact donors, those from de-eyestalked crabs exhibit greatly increased cholesterol uptake and secretion of both ecdysone and 4-min unknown in vitro. All three responses were suppressed in dose-dependent manner by eyestalk extract in the dose range, 1-4 eyestalk equivalents/Y-organ. Secretion of 4-min unknown was the response most sensitive to eyestalk extract (requiring the least dose for 50% inhibition).
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Watson RD, Spaziani E. Effects of eyestalk removal on cholesterol uptake and ecdysone secretion by crab (Cancer antennarius) Y-organs in vitro. Gen Comp Endocrinol 1985; 57:360-70. [PMID: 3988020 DOI: 10.1016/0016-6480(85)90215-1] [Citation(s) in RCA: 44] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Y-Organs and control tissues from intact (intermolt) and 48-hr de-eyestalked Cancer antennarius donors were cultured for 12 and 24 hr in crustacean saline supplemented 10% with crab serum and containing [14C]cholesterol. Under these conditions, Y-organs took up significantly more [14C]cholesterol than ovary or muscle, and Y-organs from 48-hr de-eyestalked crabs took up threefold more than Y-organs from intact crabs. The labeled cholesterol of the culture medium was observed to bind rapidly to the lipoproteins of the serum supplement; subcellular fractionation of the activated Y-organs after incubation showed 59% of the label localized in the cytosolic fraction. The increase in cholesterol uptake did not result from a change in extracellular volume, and was not accompanied by a change in Y-organ total cholesterol. It was, however, accompanied by a greater than threefold increase in ecdysone secretion.
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Vensel WH, Spaziani E, Ostedgaard LS. Cholesterol turnover and ecdysone content in tissues of normal and de-eyestalked crabs (Cancer antennarius). ACTA ACUST UNITED AC 1984. [DOI: 10.1002/jez.1402290306] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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16
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Demonstration of a molt-inhibiting hormone from the sinus gland of the lobster, Homaru americanus. ACTA ACUST UNITED AC 1984. [DOI: 10.1016/0300-9629(84)90538-3] [Citation(s) in RCA: 34] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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