Ecdysones of Plant Origin

Hara, Hiroshi; Takemoto, Tsunematsu

doi:10.1007/978-3-642-65769-6_16

Cited by 15 publications

(8 citation statements)

References 43 publications

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“…During the 1960s and 1970s, interest in the purported antitumor action of ecdysteroids led to the isolation of these compounds from various plant species (10)(11)(12)(13). The presence of ecdysone-like molecules was typically assessed by testing an extract from the plant in question in an in vivo assay in which the molting͞pupation of larvae depended on the solution possessing ecdysteroid activity (14).…”

mentioning

confidence: 99%

Identification of ligands and coligands for the ecdysone-regulated gene switch

Sáez

Nelson

Eshelman

et al. 2000

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

107

109

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The ecdysone-inducible gene switch is a useful tool for modulating gene expression in mammalian cells and transgenic animals. We have identified inducers derived from plants as well as certain classes of insecticides that increase the versatility of this gene regulation system. Phytoecdysteroids share the favorable kinetics of steroids, but are inert in mammals. The gene regulation properties of one of these ecdysteroids have been examined in cell culture and in newly developed strains of ecdysone-system transgenic mice. Ponasterone A is a potent regulator of gene expression in cells and transgenic animals, enabling reporter genes to be turned on and off rapidly. A number of nonsteroidal insecticides have been identified that also activate the ecdysone system. Because the gene-controlling properties of the ecdysone switch are based on a heterodimer composed of a modified ecdysone receptor (VgEcR) and the retinoid X receptor (RXR), we have tested the effect of RXR ligands on the VgEcR͞RXR complex. Used alone, RXR ligands display no activity on the ecdysone switch. However, when used in combination with a VgEcR ligand, RXR ligands dramatically enhance the absolute levels of induction. This property of the heterodimer has allowed the development of superinducer combinations that increase the dynamic range of the system.

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mentioning

confidence: 99%

Identification of ligands and coligands for the ecdysone-regulated gene switch

Sáez

Nelson

Eshelman

et al. 2000

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

107

109

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“…Out of all known ecdysteroids, 2 is known to have strongest affinity for the ecdysone receptor [ 31 ]. Compound 2 is well known to be involved in molting in insects and a few animals [ 32 , 33 ]. When phytoecdysteroids are produced by plants, it is widely recognized that their benefit to the producing organism is to repel insect herbivores [ 34 ].…”

Section: Resultsmentioning

confidence: 99%

Ponasterone A and F, Ecdysteroids from the Arctic Bryozoan Alcyonidium gelatinosum

et al. 2018

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A new ecdysteroid, ponasterone F (1) and the previously reported compound ponasterone A (2) were isolated from specimens of the Arctic marine bryozoan Alcyonidium gelatinosum collected at Hopenbanken, off the coast of Edgeøya, Svalbard. The structure of 1 was elucidated, and the structure of 2 confirmed by spectroscopic methods including 1D and 2D NMR and analysis of HR-MS data. The compounds were evaluated for their ability to affect bacterial survival and cell viability, as well as their agonistic activities towards the estrogen receptors α and β. The compounds were not active in these assays. Compound 2 is an arthropod hormone controlling molting and are known to act as an allelochemical when produced by plants. Even though its structure has been previously reported, this is the first time a ponasterone has been isolated from a bryozoan. A. gelatinosum produced 1 and 2 in concentrations surpassing those expected of hormonal molecules, indicating their function as defence molecules against molting predators. This work adds to the chemical diversity reported from marine bryozoans and expanded our knowledge of the chemical modifications of the ponasterones.

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“…The insect moulting hormone, ecdysone, was first isolated from an insect but it has now been isolated from over 80 families of plants and is especially abundant in ferns (HIKINO and TAKEMOTO 1974).…”

Section: Similarities Between Plants and Humansmentioning

confidence: 99%

How to produce a human with 3 chromosomes and 1000 primary genes

Lima-de-Faria

2009

Hereditas

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Bacteria, protozoa and plants have genes in common with humans. Bacteria already have blood groups. Protozoa display in organelle form most of the functions present in humans as organs. Plants produce hemoglobin, sex hormones and neurotransmitters. A metazoan may have been formed by mainly sorting out and rearranging the protozoan genes. All human cell types can be traced to only four basic tissues. Structures analogous to these tissues are already present in the protozoa. The deer Muntiacus muntjak has only 3 chromosomes, but another species, M. reevesi, has as many chromosomes as humans (n=23). Thus, genes can be reorganized into 3 or 23 chromosomes to produce essentially similar animals. Human chromosomes could be compressed into a single chromosome in terms of their DNA content. A single chromosome of Tradescantia has more DNA than the 23 human chromosomes and behaves quite well at cell division. To produce 106 functions, 106 genes are not necessary. One enzyme may have five functions, two genes may produce five enzymes, several messenger RNAs can be transcribed from a single DNA segment. Thus, 1000 primary genes may be quite enough, if not too many. There is experimental evidence that secondary genes can be produced by combination of the primary ones. From these genes multiple messenger RNAs, multiple enzymes and multiple functions can be obtained.

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Ecdysones of Plant Origin

Cited by 15 publications

References 43 publications

Identification of ligands and coligands for the ecdysone-regulated gene switch

Identification of ligands and coligands for the ecdysone-regulated gene switch

Ponasterone A and F, Ecdysteroids from the Arctic Bryozoan Alcyonidium gelatinosum

How to produce a human with 3 chromosomes and 1000 primary genes

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