Authors: Fernando PuenteSánchez Sanna Olsson Angeles Aguilera
Publish Date: 2016/08/02
Volume: 72, Issue: 3, Pages: 595-607
Abstract
Heavy metals are toxic compounds known to cause multiple and severe cellular damage However acidophilic extremophiles are able to cope with very high concentrations of heavy metals This study investigated the stress response under natural environmental heavy metal concentrations in an acidophilic Dunaliella acidophila We employed Illumina sequencing for a de novo transcriptome assembly and to identify changes in response to high cadmium concentrations and natural metalrich water The photosynthetic performance was also estimated by pulse amplitudemodulated PAM fluorescence Transcriptomic analysis highlights a number of processes mainly related to a high constitutive expression of genes involved in oxidative stress and response to reactive oxygen species ROS even in the absence of heavy metals Photosynthetic activity seems to be unaltered under shortterm exposition to Cd and chronic exposure to natural metalrich water probably due to an increase in the synthesis of structural photosynthetic components preserving their functional integrity An overrepresentation of Gene Ontology GO terms related to metabolic activities transcription and proteosomal catabolic process was observed when D acidophila grew under chronic exposure to natural metalrich water GO terms involved in carbohydrate metabolic process reticulum endoplasmic and Golgi bodies were also specifically overrepresented in natural metalrich water library suggesting an endoplasmic reticulum stress responseFunding was provided by the Spanish Ministry of Economy and Competitivity MINECO under Grants No CGL201122540 and CGL201569758 F PuenteSánchez was supported by a JAEpredoctoral fellowship Consejo Superior de Investigaciones Científicas CSIC We acknowledge the Data Intensive Academic Grid DIAG computing infrastructure funded by National Science Foundation under Grant No 0959894 titled MRIR2 Acquisition of Data Intensive Academic Grid DIAG as well as CSC – Finnish IT Center for Science and the Finnish grid infrastructure FGI for the allocation of computational resources
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