The initial tolerance to sub-lethal Cd exposure is the same among ten naïve pond populations of Daphnia magna, but their micro-evolutionary potential to develop resistance is very different

ABSTRACTGenotype-by-environment interactions (G x E) underpin the evolution of plastic responses in natural populations. Theory assumes that G x E interactions exist but empirical evidence from natural populations is equivocal and difficult to interpret because G x E interactions are normally univariate plastic responses to a single environmental gradient. We compared multivariate plastic responses of 43 Daphnia magna clones from the same population in a factorial experiment that crossed temperature and food environments. Multivariate plastic responses explained more than 30% of the total phenotypic variation in each environment. G x E interactions were detected in most environment combinations irrespective of the methodology used. However, the nature of G x E interactions was context-dependent and led to environment-specific differences in additive genetic variation (G-matrices). Clones that deviated from the population average plastic response were not the same in each environmental context and there was no difference in whether clones varied in the nature (phenotypic integration) or magnitude of their plastic response in different environments. Plastic responses to food were aligned with additive genetic variation (gmax) at both temperatures, whereas plastic responses to temperature were not aligned with additive genetic variation (gmax) in either food environment. These results suggest that fundamental differences may exist in the potential for our population to evolve novel responses to food versus temperature changes, and challenges past interpretations of thermal adaptation based on univariate studies.

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The micro-evolutionary potential of Daphnia magna population exposed to temperature and cadmium stress

Ecotoxicology and Environmental Safety ◽

10.1016/j.ecoenv.2010.05.006 ◽

2010 ◽

Vol 73 (6) ◽

pp. 1114-1122 ◽

Cited By ~ 18

Author(s):

Marlies Messiaen ◽

Karel A.C. De Schamphelaere ◽

Brita T.A. Muyssen ◽

Colin R. Janssen

Keyword(s):

Daphnia Magna ◽

Cadmium Stress ◽

Evolutionary Potential

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Bioavailability and toxicity of trace metals to the cladoceran daphnia magna in relation to CD exposure history

10.14711/thesis-b924218 ◽

2006 ◽

Author(s):

Rui Guan

Keyword(s):

Trace Metals ◽

Daphnia Magna ◽

Exposure History ◽

Cd Exposure

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Membrane-bound vesicles associated with the microvilli in the midgut of the freshwater microcrustacean, Daphnia magna

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100076135 ◽

1983 ◽

Vol 41 ◽

pp. 480-481

Author(s):

Patricia L. Jansma

Keyword(s):

Daphnia Magna ◽

Intestinal Epithelial Cells ◽

Uranyl Acetate ◽

Intestinal Epithelial ◽

Chlamydomonas Reinhardii ◽

Thin Sections ◽

Saturated Water ◽

Cacodylate Buffer ◽

Membrane Bound ◽

Ethanol Series

The presence of the membrane bound vesicles or blebs on the intestinal epithelial cells has been demonstrated in a variety of vertebrates such as chicks, piglets, hamsters, and humans. The only invertebrates shown to have these microvillar blebs are two species of f1ies. While investigating the digestive processes of the freshwater microcrustacean, Daphnia magna, the presence of these microvillar blebs was noticed.Daphnia magna fed in a suspension of axenically grown green alga, Chlamydomonas reinhardii for one hour were narcotized with CO2 saturated water. The intestinal tracts were excised in 2% glutaraldehyde in 0.2 M cacodyl ate buffer and then placed in fresh 2% glutaraldehyde for one hour. After rinsing in 0.1 M cacodylate buffer, the sample was postfixed in 2% OsO4, dehydrated with a graded ethanol series, infiltrated and embedded with Epon-Araldite. Thin sections were stained with uranyl acetate and Reynolds lead citrate before viewing with the Philips EM 200.

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Computer Reconstruction of the Cellular Architecture of the Daphnia Magna Optic Ganglion

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100115043 ◽

1975 ◽

Vol 33 ◽

pp. 284-285

Author(s):

E. R. Macagno ◽

C. Levinthal

Keyword(s):

Daphnia Magna ◽

Genetic Background ◽

Compound Eye ◽

Synaptic Connectivity ◽

Serial Sections ◽

Cross Sectional ◽

Small Crustacean ◽

Optic Ganglion ◽

Structural Invariance ◽

High Degree

The optic ganglion of Daphnia Magna, a small crustacean that reproduces parthenogenetically contains about three hundred neurons: 110 neurons in the Lamina or anterior region and about 190 neurons in the Medulla or posterior region. The ganglion lies in the midplane of the organism and shows a high degree of left-right symmetry in its structures. The Lamina neurons form the first projection of the visual output from 176 retinula cells in the compound eye. In order to answer questions about structural invariance under constant genetic background, we have begun to reconstruct in detail the morphology and synaptic connectivity of various neurons in this ganglion from electron micrographs of serial sections (1). The ganglion is sectioned in a dorso-ventra1 direction so as to minimize the cross-sectional area photographed in each section. This area is about 60 μm x 120 μm, and hence most of the ganglion fit in a single 70 mm micrograph at the lowest magnification (685x) available on our Zeiss EM9-S.

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Mise en évidence des effets sublétaux sur des populations de daphnies (Daphnia magna)

Journal français d’hydrologie ◽

10.1051/water/19811201063 ◽

1981 ◽

Vol 12 (1) ◽

pp. 63-79

Author(s):

R. Cabridenc ◽

Bui Thi ◽

H. Lepailleur

Keyword(s):

Daphnia Magna

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Melatonin protects against cadmium-induced oxidative damage in different tissues of rat: a mechanistic insight

Melatonin Research ◽

10.32794/mr11250018 ◽

2019 ◽

Vol 2 (2) ◽

pp. 1-21 ◽

Cited By ~ 3

Author(s):

Elina Mitra ◽

Bharati Bhattacharjee ◽

Palash Kumar Pal ◽

Arnab Kumar Ghosh ◽

Sanatan Mishra ◽

...

Keyword(s):

Cytochrome C ◽

Oxidative Damage ◽

Protein Carbonyl ◽

Environmental Pollutant ◽

Glutathione S Transferase ◽

Protein Carbonyl Content ◽

Wide Range ◽

Liver And Kidney ◽

Nadh Cytochrome ◽

Cd Exposure

Cadmium (Cd) is a notorious environmental pollutant known for its wide range of toxicities to organisms. Thus, the present study is designed to examine whether melatonin, a potent antioxidant, protects against Cd-induced oxidative damage in the heart, liver and kidney of rats. Cd treatment at a dose of 0.44 mg/kg for 15 days caused severe damage in all these organs. These included significantly increased activities of SGPT, SGOT, lactate dehydrogenase- 1 and 5 and ALP and levels of total lactate, creatinine, lipid peroxidation, protein carbonyl content and reduced glutathione while the activities of superoxide dismutases, catalase, glutathione peroxidase, glutathione reductase and glutathione-S-transferase along with mitochondrial pyruvate dehydrogenase, isocitrate dehydrogenase, α-keto glutarate dehydrogenase, succinate dehydrogenase, NADH-cytochrome-c-oxidoreductase and cytochrome-c-oxidase were significantly reduced by Cd. However, if melatonin was given orally 30 min before Cd injection, all these alterations induced by Cd were significantly preserved by melatonin. Histological observations also demonstrated that Cd exposure caused cellular lesions, promoting necrotic or apoptotic changes. Notably, all these changes were significantly protected by melatonin. The results suggest that melatonin is a beneficial molecule to ameliorate Cd-induced oxidative damage in the heart, liver and kidney tissues of rats with its powerful antioxidant capacity, heavy metal chelating activity and competition of binding sites with Cd to the GSH and catalase.

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