title: Linking toxicity and adaptive responses across the transcriptome, proteome, and phenotype of Chlamydomonas reinhardtii exposed to silver.
abstract: Understanding mechanistic and cellular events underlying a toxicological outcome allows the prediction of impact of environmental stressors to organisms living in different habitats. A systems-based approach aids in characterizing molecular events, and thereby the cellular pathways that have been perturbed. However, mapping only adverse outcomes of a toxicant falls short of describing the stress or adaptive response that is mounted to maintain homeostasis on perturbations and may confer resistance to the toxic insult. Silver is a potential threat to aquatic organisms because of the increasing use of silver-based nanomaterials, which release free silver ions. The effects of silver were investigated at the transcriptome, proteome, and cellular levels of Chlamydomonas reinhardtii. The cells instigate a fast transcriptome and proteome response, including perturbations in copper transport system and detoxification mechanisms. Silver causes an initial toxic insult, which leads to a plummeting of ATP and photosynthesis and damage because of oxidative stress. In response, the cells mount a defense response to combat oxidative stress and to eliminate silver via efflux transporters. From the analysis of the perturbations of the cell's functions, we derived a detailed mechanistic understanding of temporal dynamics of toxicity and adaptive response pathways for C. reinhardtii exposed to silver.
authors.affiliation: Department of Environmental Toxicology, Eawag, Swiss Federal Institute of Aquatic Science and Technology, 8600 Duebendorf, Switzerland.
authors.forename: Smitha
authors.initials: S
authors.lastname: Pillai
authors.forename: Renata
authors.initials: R
authors.lastname: Behra
authors.forename: Holger
authors.initials: H
authors.lastname: Nestler
authors.forename: Marc J-F
authors.initials: MJ
authors.lastname: Suter
authors.forename: Laura
authors.initials: L
authors.lastname: Sigg
authors.forename: Kristin
authors.initials: K
authors.lastname: Schirmer
mesh_terms: D000222:Adaptation, Physiological / Q000187:drug effects*; D000255:Adenosine Triphosphate / Q000378:metabolism; D016825:Chlamydomonas reinhardtii / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism; D020869:Gene Expression Profiling; D046228:Microarray Analysis; D010641:Phenotype; D010788:Photosynthesis / Q000187:drug effects; D020543:Proteome / Q000187:drug effects; D012834:Silver / Q000493:pharmacokinetics / Q000633:toxicity*; D013312:Stress, Physiological / Q000187:drug effects*; D059467:Transcriptome / Q000187:drug effects
chemical_list: D020543:Proteome; D012834:Silver; D000255:Adenosine Triphosphate
keywords: adaptive pathway; adverse outcome pathway; algae; systems biology; toxicity response