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Borovsky D, Van Ekert E, Buytaert E, Peeters T, Rougé P. Cloning and characterization of Aedes aegypti juvenile hormone epoxide hydrolases (JHEHs). Arch Insect Biochem Physiol 2023; 112:e21977. [PMID: 36254855 DOI: 10.1002/arch.21977] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/12/2022] [Revised: 09/26/2022] [Accepted: 09/27/2022] [Indexed: 06/16/2023]
Abstract
Juvenile hormone epoxide hydrolase (JHEH) plays an important role in the metabolism of juvenile hormone III (JH III) in insects. To study the role that JHEH plays in female Aedes aegypti JHEH 1, 2, and 3 complementary DNA (cDNAs) were cloned and sequenced. Northern blot analyses show that the three transcripts are expressed in the head thorax, the gut, the ovaries, and the fat body of females. Molecular modeling shows that the enzyme is a homodimer that binds JH III acid (JH IIIA) at the catalytic groove better than JH III. The cDNA of JHEH 1 and 2 are very similar indicating close relationship. Knocking down of jheh 1, 2, and 3 in adult female and larval Ae. aegypti using double-stranded RNA (dsRNA) did not affect egg development or caused adult mortality. Larvae that were fed bacterial cells expressing dsRNA against jheh 1, 2, and 3 grew normally. Treating blood-fed female Ae. aegypti with [12-3 H](10R) JH III and analyzing the metabolites by C18 reversed phase chromatography showed that JHEH preferred substrate is not JH III but JH IIIA. Genomic analysis of jheh 1, 2, and 3 indicate that jheh 1 and 2 are transcribed from a 1.53 kb DNA whereas jheh 3 is transcribed from a 10.9 kb DNA. All three genes are found on chromosome two at distinct locations. JHEH 2 was expressed in bacterial cells and purified by Ni affinity chromatography. Sequencing of the recombinant protein by MS/MS identified JHEH 2 as the expressed recombinant protein.
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Affiliation(s)
- Dov Borovsky
- Department of Biochemistry and Molecular Genetics, University of Colorado Anschutz Medical Campus, Aurora, Colorado, USA
| | | | | | - Tom Peeters
- Open BioLab Brussels, Erasmushogeschool, Brussels, Belgium
| | - Pierre Rougé
- Faculte des Sciences Pharmaceutiques, Toulouse, France
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de Melo Barros S, Van Ekert E, Whitaker SK, Avila LA, Stewart W, Gillian J, Aulisa L, Tomich JM. Bio‐lethal effect of BAPCs‐dsRNA formulations for genetics‐based pest management. FASEB J 2020. [DOI: 10.1096/fasebj.2020.34.s1.09775] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Van Ekert E, Chauvigné F, Finn RN, Mathew LG, Hull JJ, Cerdà J, Fabrick JA. Molecular and functional characterization of Bemisia tabaci aquaporins reveals the water channel diversity of hemipteran insects. Insect Biochem Mol Biol 2016; 77:39-51. [PMID: 27491441 DOI: 10.1016/j.ibmb.2016.07.010] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/02/2016] [Revised: 07/28/2016] [Accepted: 07/31/2016] [Indexed: 06/06/2023]
Abstract
The Middle East-Asia Minor 1 (MEAM1) whitefly, Bemisia tabaci (Gennadius) is an economically important pest of food, fiber, and ornamental crops. This pest has evolved a number of adaptations to overcome physiological challenges, including 1) the ability to regulate osmotic stress between gut lumen and hemolymph after imbibing large quantities of a low nitrogen, sugar-rich liquid diet; 2) the ability to avoid or prevent dehydration and desiccation, particularly during egg hatching and molting; and 3) to be adapted for survival at elevated temperatures. One superfamily of proteins involved in the maintenance of fluid homeostasis in many organisms includes the aquaporins, which are integral membrane channel proteins that aid in the rapid flux of water and other small solutes across biological membranes. Here, we show that B. tabaci has eight aquaporins (BtAqps), of which seven belong to the classical aquaporin 4-related grade of channels, including Bib, Drip, Prip, and Eglps and one that belongs to the unorthodox grade of aquaporin 12-like channels. B. tabaci has further expanded its repertoire of water channels through the expression of three BtDrip2 amino-terminal splice variants, while other hemipteran species express amino- or carboxyl-terminal isoforms of Drip, Prip, and Eglps. Each BtAqp has unique transcript expression profiles, cellular localization, and/or substrate preference. Our phylogenetic and functional data reveal that hemipteran insects lost the classical glp genes, but have compensated for this by duplicating the eglp genes early in their evolution to comprise at least three separate clades of glycerol transporters.
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Affiliation(s)
- Evelien Van Ekert
- USDA-ARS, U.S. Arid Land Agricultural Research Center, Maricopa, AZ 85138, USA
| | - François Chauvigné
- Department of Biology, Bergen High Technology Centre, University of Bergen, 5020 Bergen, Norway; Institut de Recerca i Tecnologia Agroalimentaries (IRTA)-Institut de Ciencies del Mar, Consejo Superior de Investigaciones Cientificas (CSIC), 08003 Barcelona, Spain
| | - Roderick Nigel Finn
- Department of Biology, Bergen High Technology Centre, University of Bergen, 5020 Bergen, Norway; Institute of Marine Research, Nordnes, 5817 Bergen, Norway
| | - Lolita G Mathew
- USDA-ARS, U.S. Arid Land Agricultural Research Center, Maricopa, AZ 85138, USA
| | - J Joe Hull
- USDA-ARS, U.S. Arid Land Agricultural Research Center, Maricopa, AZ 85138, USA
| | - Joan Cerdà
- Institut de Recerca i Tecnologia Agroalimentaries (IRTA)-Institut de Ciencies del Mar, Consejo Superior de Investigaciones Cientificas (CSIC), 08003 Barcelona, Spain
| | - Jeffrey A Fabrick
- USDA-ARS, U.S. Arid Land Agricultural Research Center, Maricopa, AZ 85138, USA.
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Van Ekert E, Shatters RG, Rougé P, Powell CA, Smagghe G, Borovsky D. Cloning and expressing a highly functional and substrate specific farnesoic acid o-methyltransferase from the Asian citrus psyllid (Diaphorina citri Kuwayama). FEBS Open Bio 2015; 5:264-75. [PMID: 25893162 PMCID: PMC4398755 DOI: 10.1016/j.fob.2015.03.012] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2015] [Revised: 03/26/2015] [Accepted: 03/26/2015] [Indexed: 10/29/2022] Open
Abstract
The Asian citrus psyllid, Diaphorina citri, transmits a phloem-limited bacterium, Candidatus 'Liberibacter' asiaticus that causes citrus greening disease. Because juvenile hormone (JH) plays an important role in adult and nymphal development, we studied the final steps in JH biosynthesis in D. citri. A putative JH acid methyltransferase ortholog gene (jmtD) and its cognate cDNA were identified by searching D. citri genome database. Expression analysis shows expression in all life stages. In adults, it is expressed in the head-thorax, (containing the corpora allata), and the abdomen (containing ovaries and male accessory glands). A 3D protein model identified the catalytic groove with catalytically active amino acids and the S-adenosyl methionine (SAM)-binding loop. The cDNA was expressed in Escherichia coli cells and the purified enzyme showed high preference for farnesoic acid (FA) and homoFA (kcat of 0.752 × 10(-3) and 0.217 × 10(-3) s(-1), respectively) as compared to JH acid I (JHA I) (cis/trans/cis; 2Z, 6E, 10cis), JHA III (2E, 6E, 10cis), and JHA I (trans/cis/cis; 2E, 2Z, 10cis) (kcat of 0.081 × 10(-3), 0.013 × 10(-3), and 0.003 × 10(-3) s(-1), respectively). This suggests that this ortholog is a DcFA-o-methyl transferase gene (fmtD), not a jmtD, and that JH biosynthesis in D. citri proceeds from FA to JH III through methyl farnesoate (MF). DcFA-o-MT does not require Ca(2+), Mg(2+) or Zn(2+), however, Zn(2+) (1 mM) completely inhibits the enzyme probably by binding H115 at the active groove. This represents the first purified FA-o-MT from Hemiptera with preferred biological activity for FA and not JHA.
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Key Words
- 3D modeling
- Diaphorina citri
- FA, farnesoic acid
- FA-o-MT, farnesoic acid o-methyltransferase
- Farnesoic acid methyltransferase
- GAPDH, glyceraldehyde 3-phosphate dehydrogenase
- Gene expression
- JH, juvenile hormone
- JHA, juvenile hormone acid
- JHAMT, juvenile hormone acid methyltransferase
- Juvenile hormone acid methyltransferase
- MF, methyl farnesoate
- MMLV, Moloney murine leukemia virus
- RP, reversed phase
- SAM, S-adenosyl methionine
- SAM-MT, S-adenosyl methionine-dependent methyltransferase
- fmtD, Diaphorina citri farnesoic acid o-methyltransferase gene
- jmtD, juvenile hormone acid methyl transferase ortholog gene of Diaphorina citri
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Affiliation(s)
| | | | - Pierre Rougé
- Université de Toulouse, UPS, Institut de Recherche pour le Développement (IRD), UMR 152 Pharma-Dev, Université Toulouse 3, Faculté des Sciences Pharmaceutiques, F-31062 Toulouse cedex 09, France
| | - Charles A Powell
- Indian River Research and Education Center, University of Florida, FL 34945, USA
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Van Ekert E, Powell CA, Shatters RG, Borovsky D. Control of larval and egg development in Aedes aegypti with RNA interference against juvenile hormone acid methyl transferase. J Insect Physiol 2014; 70:143-150. [PMID: 25111689 DOI: 10.1016/j.jinsphys.2014.08.001] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/07/2014] [Revised: 07/31/2014] [Accepted: 08/02/2014] [Indexed: 06/03/2023]
Abstract
RNA interference (RNAi) is a powerful approach for elucidating gene functions in a variety of organisms, including mosquitoes and many other insects. Little has been done, however, to harness this approach in order to control adult and larval mosquitoes. Juvenile hormone (JH) plays a pivotal role in the control of reproduction in adults and metamorphism in larval mosquitoes. This report describes an approach to control Aedes aegypti using RNAi against JH acid methyl transferase (AeaJHAMT), the ultimate enzyme in the biosynthetic pathway of JH III that converts JH acid III (JHA III) into JH III. In female A. aegypti that were injected or fed jmtA dsRNA targeting the AeaJHAMT gene (jmtA) transcript, egg development was inhibited in 50% of the treated females. In mosquito larvae that were fed transgenic Pichia pastoris cells expressing long hair pin (LHP) RNA, adult eclosion was delayed by 3 weeks causing high mortality. Northern blot analyses and qPCR studies show that jmtA dsRNA causes inhibition of jmtA transcript in adults and larvae, which is consistent with the observed inhibition of egg maturation and larval development. Taken together, these results suggest that jmtA LHP RNA expressed in heat inactivated genetically modified P. pastoris cells could be used to control mosquito populations in the marsh.
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Affiliation(s)
- Evelien Van Ekert
- Indian River Research and Education Center, University of Florida, FL 34945, USA
| | - Charles A Powell
- Indian River Research and Education Center, University of Florida, FL 34945, USA
| | | | - Dov Borovsky
- Borovsky Consulting, 135 36th Court, Vero Beach, FL 32968, USA.
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Van Ekert E, Heylen K, Rougé P, Powell CA, Shatters RG, Smagghe G, Borovsky D. Aedes aegypti juvenile hormone acid methyl transferase, the ultimate enzyme in the biosynthetic pathway of juvenile hormone III, exhibits substrate control. J Insect Physiol 2014; 64:62-73. [PMID: 24657668 DOI: 10.1016/j.jinsphys.2014.03.001] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/25/2013] [Revised: 03/02/2014] [Accepted: 03/06/2014] [Indexed: 06/03/2023]
Abstract
We report on the cloning, sequencing, characterization, 3D modeling and docking of Aedes aegypti juvenile hormone acid methyl transferase (AeaJHAMT), the enzyme that converts juvenile hormone acid (JHA) into juvenile hormone (JH). Purified recombinant AeaJHAMT was extensively characterized for enzymatic activity and the Michaelis Menten kinetic parameters Km, Vmax, k(cat) (turn over number) and k(cat)/Km (catalytic efficiency) using JHA and its analogues as substrates. AeaJHAMT methylates JHA III 5-fold faster than farnesoic acid (FA). Significant differences in lower methyl transferase (MT) activities towards the cis/trans/trans, cis/trans/cis and the trans/cis/cis isomers of JHA I (1.32, 4.71 and 156-fold, respectively) indicate that substrate chirality is important for proper alignment at the catalytic cavity and for efficient methyl transfer by S-adenosyl methionine (SAM). Our 3D model shows a potential binding site below the main catalytic cavity for JHA analogues causing conformational change and steric hindrance in the transfer of the methyl group to JHA III. These, in silico, observations were corroborated by, in vitro, studies showing that several JHA analogues are potent inhibitors of AeaJHAMT. In vitro, and in vivo studies using [(3)H-methyl]SAM show that the enzyme is present and active throughout the adult life stage of A. aegypti. Tissue specific expressions of the JHAMT gene of A. aegypti (jmtA) transcript during the life cycle of A. aegypti show that AeaJHAMT is a constitutive enzyme and jmtA transcript is expressed in the corpora allata (CA), and the ovary before and after the blood meal. These results indicate that JH III can be synthesized from JHA III by the mosquito ovary, suggesting that ovarian JH III may play an important physiological role in ovarian development and reproduction. Incubating AeaJHAMT with highly pure synthetic substrates indicates that JHA III is the enzyme's preferred substrate, suggesting that AeaJHAMT is the ultimate enzyme in the biosynthetic pathway of JH III.
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Affiliation(s)
- Evelien Van Ekert
- Indian River Research and Education Center, University of Florida, FL 34945, USA
| | - Kevin Heylen
- Katholieke Universiteit Leuven, Leuven B-3000, Belgium
| | - Pierre Rougé
- UMR UPS-IRD 152, Université Paul Sabatier, Toulouse 3106, France
| | - Charles A Powell
- Indian River Research and Education Center, University of Florida, FL 34945, USA
| | | | | | - Dov Borovsky
- Borovsky Consulting, 135 36th Court, Vero Beach, FL 32968, USA.
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