An omics based assessment of cadmium toxicity in the green alga Chlamydomonas reinhardtii

Jamers, An; Blust, Ronny; Coen, Wim De; Griffin, Julian L.; Jones, Oliver A.H.

doi:10.1016/j.aquatox.2012.09.007

Cited by 126 publications

(70 citation statements)

References 46 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…S2 in the supplemental material). Similar amounts of these two metals have previously been shown to alter gene expression in Chlamydomonas (29,(65)(66)(67), although to our knowledge no effect on autophagy genes in algae or plants has been reported. However, cadmium toxicity has been linked to the activation of autophagy in human cells on the basis of the tumorigenic and cell death-inducing properties of this metal (68).…”

Section: Discussionmentioning

confidence: 78%

“…Moreover, carotenoid depletion in Chlamydomonas causes ROS accumulation, which in turn triggers autophagy (21). Metal toxicity has been associated with ROS production and oxidative stress signaling in plants and algae (28)(29)(30)(31)(32), but it remains unknown whether the cellular response to metals in these organisms may include the activation of autophagy. Chlamydomonas has been widely used to investigate metal metabolism and the cellular response to metal excess and metal-limiting conditions (28,33,34), and the development of genome-wide technologies has increased our current understanding about metal signaling in this alga.…”

mentioning

confidence: 99%

See 1 more Smart Citation

Activation of Autophagy by Metals in Chlamydomonas reinhardtii

et al. 2015

View full text Add to dashboard Cite

Autophagy is an intracellular self-degradation pathway by which eukaryotic cells recycle their own material in response to specific stress conditions. Exposure to high concentrations of metals causes cell damage, although the effect of metal stress on autophagy has not been explored in photosynthetic organisms. In this study, we investigated the effect of metal excess on autophagy in the model unicellular green alga Chlamydomonas reinhardtii. We show in cells treated with nickel an upregulation of ATG8 that is independent of CRR1, a global regulator of copper signaling in Chlamydomonas. A similar effect on ATG8 was observed with copper and cobalt but not with cadmium or mercury ions. Transcriptome sequencing data revealed an increase in the abundance of the protein degradation machinery, including that responsible for autophagy, and a substantial overlap of that increased abundance with the hydrogen peroxide response in cells treated with nickel ions. Thus, our results indicate that metal stress triggers autophagy in Chlamydomonas and suggest that excess nickel may cause oxidative damage, which in turn activates degradative pathways, including autophagy, to clear impaired components and recover cellular homeostasis. Eukaryotic cells are able to degrade and recycle their own material when they are exposed to nutrient starvation or other adverse conditions through a catabolic pathway known as macroautophagy or autophagy. This process is characterized by the formation of double-membrane vesicles termed autophagosomes that engulf and deliver cytosolic components to the vacuole/lysosome for degradation (1-4). The primary function of autophagy is to recycle cytoplasmic material as well as to clear damaged organelles or toxic cellular components generated during stress in order to maintain cellular homeostasis. In higher eukaryotes, autophagy has also been implicated in cell differentiation, development and cell death, and several human pathologies, such as cancer and neurodegenerative diseases (5, 6).Autophagy is mediated by highly conserved autophagy-related (ATG) genes, which have been described in organisms ranging from yeasts to mammals. Some ATG proteins are required for the formation of the autophagosome and constitute the core autophagy machinery (4,7,8). This group of proteins includes the ATG8 and ATG12 ubiquitin-like systems required for vesicle expansion. The ATG8 protein has been widely used to monitor autophagy in many systems (9) because, unlike other ATG proteins, this protein firmly binds to the autophagosome membrane through a covalent bond to phosphatidylethanolamine (PE). Most of the core ATG proteins are conserved in land plants (10-12) and in evolutionarily distant algae, including freshwater species, such as the model green alga Chlamydomonas reinhardtii (herein referred to as Chlamydomonas) (13) and marine species (14). Our current knowledge about autophagy in algae is still limited compared to our knowledge about autophagy in other eukaryotes, but recent studies, mainly performed in Chlamydomon...

show abstract

Section: Discussionmentioning

confidence: 78%

mentioning

confidence: 99%

Activation of Autophagy by Metals in Chlamydomonas reinhardtii

et al. 2015

View full text Add to dashboard Cite

show abstract

“…But Jamers et al (2013) found that 8.1 lM total Cd could increase C. reinhardtii growth rate by 2.25%. Moreover, 0.02 lM free Cd 2+ ion could increase maximum Chlorella vulgaris growth rate and maximum total lipids by 13.43% and 51.53% respectively at different PO 4 3-concentrations (Chia et al, 2013), but the real mechanism was still unclear.…”

Section: Algae Growth Lipid Accumulation and Heavy Metal Removalmentioning

confidence: 95%

Lipid production combined with biosorption and bioaccumulation of cadmium, copper, manganese and zinc by oleaginous microalgae Chlorella minutissima UTEX2341

Yang

Cao

Xing

et al. 2015

Bioresource Technology

271

View full text Add to dashboard Cite

“…Cadmium (Cd) is a widespread metal pollutant owing to its high toxicity, easy absorption, non-biodegradability and accumulation in the food chain (Jamers et al 2013). Approximately 1 9 10 4 t of Cd is released into the environment each year by a growing number of industrial effluents and wastes, urban runoff, sewage treatment plants, boating activities, agricultural fungicide runoff, domestic garbage dumps, and mining operations (Ji et al 2001).…”

Section: Introductionmentioning

confidence: 99%

Assessment of growth rate, chlorophyll a fluorescence, lipid peroxidation and antioxidant enzyme activity in Aphanizomenon flos-aquae, Pediastrum simplex and Synedra acus exposed to cadmium

Ran

Liu

et al. 2014

Ecotoxicology

View full text Add to dashboard Cite

In this study, the effects of cadmium on the cyanobacterium Aphanizomenon flos-aquae, the green alga Pediastrum simplex and the diatom Synedra acus was evaluated on the basis of growth rate, chlorophyll a fluorescence, lipid peroxidation and antioxidant enzyme activity. The EC50 values (effective concentration inducing 50 % of growth inhibition) of cadmium in A. flos-aquae, P. simplex and S. acus were 1.18 ± 0.044, 4.32 ± 0.068 and 3.7 ± 0.055 mg/L, respectively. The results suggested that cadmium stress decreases growth rate and chlorophyll a concentration. The normalized chlorophyll a fluorescence transients significantly increased at cadmium concentrations of 5.0, 10.0 and 20.0 mg/L, but slightly decreased at concentrations of 0.2, 0.5 and 1.0 mg/L. The chlorophyll fluorescence parameters showed considerable variation among the three species, while lipid peroxidation and antioxidant enzyme activities showed a significant increase. Our results demonstrated that blockage of electron transport on the acceptor side of photosystem II is the mechanism responsible for cadmium toxicity in freshwater microalgae, and that the tolerance of the three species to cadmium was in the order green alga P. simplex > diatom S. acus > cyanobacterium A. flos-aquae.

show abstract

An omics based assessment of cadmium toxicity in the green alga Chlamydomonas reinhardtii

Cited by 126 publications

References 46 publications

Activation of Autophagy by Metals in Chlamydomonas reinhardtii

Activation of Autophagy by Metals in Chlamydomonas reinhardtii

Lipid production combined with biosorption and bioaccumulation of cadmium, copper, manganese and zinc by oleaginous microalgae Chlorella minutissima UTEX2341

Assessment of growth rate, chlorophyll a fluorescence, lipid peroxidation and antioxidant enzyme activity in Aphanizomenon flos-aquae, Pediastrum simplex and Synedra acus exposed to cadmium

Contact Info

Product

Resources

About