1
|
Burger H, Buttala S, Koch H, Ayasse M, Johnson SD, Stevenson PC. Nectar cardenolides and floral volatiles mediate a specialized wasp pollination system. J Exp Biol 2024; 227:jeb246156. [PMID: 38180227 PMCID: PMC10785657 DOI: 10.1242/jeb.246156] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2023] [Accepted: 11/15/2023] [Indexed: 01/06/2024]
Abstract
Specialization in plant pollination systems can arise from traits that function as filters of flower visitors. This may involve chemical traits such as floral volatiles that selectively attract favoured visitors and non-volatile nectar constituents that selectively deter disfavoured visitors through taste or longer-term toxic effects or both. We explored the functions of floral chemical traits in the African milkweed Gomphocarpus physocarpus, which is pollinated almost exclusively by vespid wasps, despite having nectar that is highly accessible to other insects such as honeybees. We demonstrated that the nectar of wasp-pollinated G. physocarpus contains cardenolides that had greater toxic effects on Apis mellifera honeybees than on Vespula germanica wasps, and also reduced feeding rates by honeybees. Behavioural experiments using natural compositions of nectar compounds showed that these interactions are mediated by non-volatile nectar chemistry. We also identified volatile compounds with acetic acid as a main component in the floral scent of G. physocarpus that elicited electrophysiological responses in wasp antennae. Mixtures of these compounds were behaviourally effective for attraction of V. germanica wasps. The results show the importance of both volatile and non-volatile chemical traits as filters that lead to specialization in plant pollination systems.
Collapse
Affiliation(s)
- Hannah Burger
- Evolutionary Ecology and Conservation Genomics, Ulm University, 89081 Ulm, Germany
| | - Samantha Buttala
- Evolutionary Ecology and Conservation Genomics, Ulm University, 89081 Ulm, Germany
| | - Hauke Koch
- Royal Botanic Gardens, Kew,Kew Green, Richmond TW9 3AE, UK
| | - Manfred Ayasse
- Evolutionary Ecology and Conservation Genomics, Ulm University, 89081 Ulm, Germany
| | - Steven D. Johnson
- Centre for Functional Biodiversity, School of Life Sciences, University of KwaZulu-Natal, Scottsville, Pietermaritzburg 3209, South Africa
| | - Philip C. Stevenson
- Royal Botanic Gardens, Kew,Kew Green, Richmond TW9 3AE, UK
- Natural Resources Institute, University of Greenwich, Chatham Maritime, Kent ME4 4TB, UK
| |
Collapse
|
2
|
War AR, Buhroo AA, Hussain B, Ahmad T, Nair RM, Sharma HC. Plant Defense and Insect Adaptation with Reference to Secondary Metabolites. REFERENCE SERIES IN PHYTOCHEMISTRY 2020. [DOI: 10.1007/978-3-319-96397-6_60] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
|
3
|
Petschenka G, Fei CS, Araya JJ, Schröder S, Timmermann BN, Agrawal AA. Relative Selectivity of Plant Cardenolides for Na +/K +-ATPases From the Monarch Butterfly and Non-resistant Insects. FRONTIERS IN PLANT SCIENCE 2018; 9:1424. [PMID: 30323822 PMCID: PMC6172315 DOI: 10.3389/fpls.2018.01424] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/25/2018] [Accepted: 09/07/2018] [Indexed: 05/31/2023]
Abstract
A major prediction of coevolutionary theory is that plants may target particular herbivores with secondary compounds that are selectively defensive. The highly specialized monarch butterfly (Danaus plexippus) copes well with cardiac glycosides (inhibitors of animal Na+/K+-ATPases) from its milkweed host plants, but selective inhibition of its Na+/K+-ATPase by different compounds has not been previously tested. We applied 17 cardiac glycosides to the D. plexippus-Na+/K+-ATPase and to the more susceptible Na+/K+-ATPases of two non-adapted insects (Euploea core and Schistocerca gregaria). Structural features (e.g., sugar residues) predicted in vitro inhibitory activity and comparison of insect Na+/K+-ATPases revealed that the monarch has evolved a highly resistant enzyme overall. Nonetheless, we found evidence for relative selectivity of individual cardiac glycosides reaching from 4- to 94-fold differences of inhibition between non-adapted Na+/K+-ATPase and D. plexippus-Na+/K+-ATPase. This toxin receptor specificity suggests a mechanism how plants could target herbivores selectively and thus provides a strong basis for pairwise coevolutionary interactions between plants and herbivorous insects.
Collapse
Affiliation(s)
- Georg Petschenka
- Institute for Insect Biotechnology, Justus-Liebig-Universität, Giessen, Germany
| | - Colleen S. Fei
- Department of Ecology and Evolutionary Biology, Cornell University, Ithaca, NY, United States
| | - Juan J. Araya
- Centro de Investigaciones en Productos Naturales, Escuela de Química, Instituto de Investigaciones Farmacéuticas, Facultad de Farmacia, Universidad de Costa Rica, San Pedro, Costa Rica
| | - Susanne Schröder
- Institut für Medizinische Biochemie und Molekularbiologie, Universität Rostock, Rostock, Germany
| | - Barbara N. Timmermann
- Department of Medicinal Chemistry, School of Pharmacy, University of Kansas, Lawrence, KS, United States
| | - Anurag A. Agrawal
- Department of Ecology and Evolutionary Biology, Cornell University, Ithaca, NY, United States
| |
Collapse
|
4
|
Pierce AA, de Roode JC, Tao L. Comparative genetics of Na +/K +-ATPase in monarch butterfly populations with varying host plant toxicity. Biol J Linn Soc Lond 2016. [DOI: 10.1111/bij.12797] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Amanda A. Pierce
- Department of Biology; Emory University; 1510 Clifton Road Atlanta GA 30322 USA
| | - Jacobus C. de Roode
- Department of Biology; Emory University; 1510 Clifton Road Atlanta GA 30322 USA
| | - Leiling Tao
- Department of Biology; Emory University; 1510 Clifton Road Atlanta GA 30322 USA
| |
Collapse
|
5
|
Holzinger F, Wink M. Mediation of cardiac glycoside insensitivity in the monarch butterfly (Danaus plexippus): Role of an amino acid substitution in the ouabain binding site of Na(+),K (+)-ATPase. J Chem Ecol 2013; 22:1921-37. [PMID: 24227116 DOI: 10.1007/bf02028512] [Citation(s) in RCA: 68] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/1996] [Accepted: 05/16/1996] [Indexed: 12/01/2022]
Abstract
The Monarch butterfly (Danaus plexippus) sequesters cardiac glycosides (CG) for its chemical defense against predators. Larvae and adults of this butterfly are insensitive towards dietary cardiac glycosides, whereas other Lepidoptera are sensitive and intoxicated by ouabain. Ouabain inhibits Na(+),K(+)-ATPase by binding to its α-subunit. We have amplified and cloned the DNA-sequence encoding the respective ouabain binding site. Instead of the amino acid asparagine at position 122 in ouabain-sensitive insects, the Monarch has a histidine in the putative ouabain binding site, which consists of 12 amino acids. Starting with the CG-sensitive Na(+),K(+)-ATPase gene fromDrosophila, we converted pos. 122 to a histidine residue as inDanaus plexippus by site-directed mutagenesis. Human embryonic kidney cells (HEK) (which are sensitive to ouabain) were transfected with the mutated Na(+),K(+)-ATPase gene in a pSVDF-expression vector and showed a transient expression of the mutatedDrosophila Na(+),K(+)-ATPase. When treated with ouabain, the transfected cells tolerated ouabain at a concentration of 50 mM, whereas untransformed controls or controls transfected with the unmutatedDrosophila gene, showed a substantial mortality. This result implies that the asparagine to histidine exchange contributes to ouabain insensitivity in the Monarch. In two other CG-sequestering insects, e.g.,Danaus gilippus andSyntomeida epilais, the pattern of amino acid substitution differed, indicating that the Monarch has acquired this mutation independently during evolution.
Collapse
Affiliation(s)
- F Holzinger
- Institut für Pharmazeutische Biologie, Universität Heidelberg, Im Neuenheimer Feld 364, D-69120, Heidelberg, Germany
| | | |
Collapse
|
6
|
Selective sequestration of cardenolide isomers by two species of Danaus butterflies (Lepidoptera: Nymphalidae: Danainae). CHEMOECOLOGY 2012. [DOI: 10.1007/s00049-012-0109-7] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
|
7
|
Agrawal AA, Petschenka G, Bingham RA, Weber MG, Rasmann S. Toxic cardenolides: chemical ecology and coevolution of specialized plant-herbivore interactions. THE NEW PHYTOLOGIST 2012; 194:28-45. [PMID: 22292897 DOI: 10.1111/j.1469-8137.2011.04049.x] [Citation(s) in RCA: 227] [Impact Index Per Article: 18.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
Cardenolides are remarkable steroidal toxins that have become model systems, critical in the development of theories for chemical ecology and coevolution. Because cardenolides inhibit the ubiquitous and essential animal enzyme Na⁺/K⁺-ATPase, most insects that feed on cardenolide-containing plants are highly specialized. With a huge diversity of chemical forms, these secondary metabolites are sporadically distributed across 12 botanical families, but dominate the Apocynaceae where they are found in > 30 genera. Studies over the past decade have demonstrated patterns in the distribution of cardenolides among plant organs, including all tissue types, and across broad geographic gradients within and across species. Cardenolide production has a genetic basis and is subject to natural selection by herbivores. In addition, there is strong evidence for phenotypic plasticity, with the biotic and abiotic environment predictably impacting cardenolide production. Mounting evidence indicates a high degree of specificity in herbivore-induced cardenolides in Asclepias. While herbivores of cardenolide-containing plants often sequester the toxins, are aposematic, and possess several physiological adaptations (including target site insensitivity), there is strong evidence that these specialists are nonetheless negatively impacted by cardenolides. While reviewing both the mechanisms and evolutionary ecology of cardenolide-mediated interactions, we advance novel hypotheses and suggest directions for future work.
Collapse
Affiliation(s)
- Anurag A Agrawal
- Department of Ecology and Evolutionary Biology, and Department of Entomology, Cornell University, Ithaca, NY 14853, USA
| | - Georg Petschenka
- Biozentrum Grindel, Molekulare Evolutionsbiologie, Martin-Luther-King Platz 3, 20146 Hamburg, Germany
| | - Robin A Bingham
- Department of Natural and Environmental Sciences, Western State College of Colorado, Gunnison, CO 81231, USA
| | - Marjorie G Weber
- Department of Ecology and Evolutionary Biology, and Department of Entomology, Cornell University, Ithaca, NY 14853, USA
| | - Sergio Rasmann
- Department of Ecology and Evolution, Bâtiment Biophore, University of Lausanne, CH - 1015 Lausanne, Switzerland
| |
Collapse
|
8
|
Balsevich JJ, Bishop GG, Deibert LK. Use of digitoxin and digoxin as internal standards in HPLC analysis of triterpene saponin-containing extracts. PHYTOCHEMICAL ANALYSIS : PCA 2009; 20:38-49. [PMID: 18819105 DOI: 10.1002/pca.1095] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
INTRODUCTION Saponins are widely distributed complex plant glycosides possessing a variety of structure-dependent bioactivities. Quantitation of individual saponins is difficult due to lack of available standards, mainly as a consequence of purification difficulties. Determination of total saponin content can be problematic, often relying on non-specific methods based on butanol solubility, haemolytic activity or formation of coloured derivatives. OBJECTIVE To develop a general quantitative method based on the use of the readily available cardenolides, digitoxin (1) and digoxin (2), as internal standards in an HPLC-PAD-based analysis. METHODOLOGY The cardenolides were run at a variety of concentrations to establish linearity and reproducibility of detector response and then evaluated as internal standards for quantitation of triterpene saponins in several plant-derived extracts by HPLC-PAD. Mixtures of saponins, largely freed from other extractables, were obtained by fractionation of total extracts on solid phase extraction columns (SPE) employing a water-methanol gradient and used for construction of calibration curves. Saponin identification and structural information was obtained via a single quadrupole mass detector using electrospray ionisation in negative ion mode (ESI(-)). RESULTS Saponin contents in six samples from five species were determined and compared with literature results and a gravimetric method based on butanol-water partitioning. Results were generally consistent with literature reports and superior to gravimetric butanol-water partitioning. CONCLUSION Digitoxin and digoxin are useful as internal standards in HPLC estimation of saponin content. Saponins from different species having similar structures and molecular weights afford similar calibration curves.
Collapse
Affiliation(s)
- J John Balsevich
- Plant Biotechnology Institute, National Research Council of Canada, 110 Gymnasium Place, Saskatoon, SK, Canada
| | | | | |
Collapse
|
9
|
Abstract
A number of aposematic butterfly and diurnal moth species sequester unpalatable or toxic substances from their host plants rather than manufacturing their own defensive substances. Despite a great diversity in their life histories, there are some general features in the selective utilization of plant secondary metabolites to achieve effective protection from predators. This review illustrates the biochemical, physiological, and ecological characteristics of phytochemical-based defense systems that can shed light on the evolution of the widely developed sequestering lifestyles among the Lepidoptera.
Collapse
Affiliation(s)
- Ritsuo Nishida
- Laboratory of Chemical Ecology, Graduate School of Agriculture, Kyoto University, Kyoto 606-8502, Japan.
| |
Collapse
|
10
|
Abstract
In this review, we consider the general principles and specific methods for the purification of different classes of phytosteroids which have been isolated from plant sources: brassinosteroids, bufadienolides, cardenolides, cucurbitacins, ecdysteroids, steroidal saponins, steroidal alkaloids, vertebrate-type steroids and withanolides. For each class we give a brief summary of the characteristic structural features, their distribution in the plant world and their biological effects and applications. Most classes are associated with one or a few plant families, e.g., the withanolides with the Solanaceae, but others, e.g., the saponins, are very widespread. Where a compound class has been extensively studied, a large number of analogues are present across a range of species. We discuss the general principles for the isolation of plant steroids. The predominant methods for isolation are solvent extraction/partition followed by column chromatography and thin-layer chromatography/HPLC.
Collapse
Affiliation(s)
- L Dinan
- Department of Biological Sciences, University of Exeter, Hatherly Laboratories, Devon, UK.
| | | | | |
Collapse
|
11
|
Frick C, Wink M. Uptake and sequestration of ouabain and other cardiac glycosides inDanaus plexippus (Lepidoptera: Danaidae): Evidence for a carrier-mediated process. J Chem Ecol 1995; 21:557-75. [DOI: 10.1007/bf02033701] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/1994] [Accepted: 01/26/1995] [Indexed: 11/24/2022]
|