ABSTRACT: Identification of genes involved in heavy metal tolerance and transcriptomic changes caused by copper excess in the extremophilic green alga Chlamydomonas acidophila
Project description:MAP kinases are integral to the mechanisms by which cells respond to a wide variety of environmental stresses. In Caenorhabditis elegans, the KGB-1 JNK signaling pathway regulates the response to heavy metal stress. The deletion mutants of this cascade show hypersensitivity to heavy metals like copper or cadmium. However, factors that function downstream of KGB-1 pathway are not well characterized. To understand how the KGB-1 pathway modulates gene activity and to define the physiological processes in which the heavy metal stress response may be involved, we used microarray to examine gene expression changes in wild-type and kgb-1 mutant animals subjected to heavy metal stress. Adult worms of WT or kgb-1 mutant were incubated with H2O or 1 mM copper sulfate for 1 hour. Total RNA was then prepared using Trizol reagent (Invitrogen), followed by DNase I treatment, phenol/chloroform extraction and ethanol precipitation. (WT_Cu-), (WT_Cu+), (kgb-1_Cu-) and (kgb-1_Cu+) RNAs extraction were hybridized on Affymetrix microarrays.
Project description:MAP kinases are integral to the mechanisms by which cells respond to a wide variety of environmental stresses. In Caenorhabditis elegans, the KGB-1 JNK signaling pathway regulates the response to heavy metal stress. The deletion mutants of this cascade show hypersensitivity to heavy metals like copper or cadmium. However, factors that function downstream of KGB-1 pathway are not well characterized. To understand how the KGB-1 pathway modulates gene activity and to define the physiological processes in which the heavy metal stress response may be involved, we used microarray to examine gene expression changes in wild-type and kgb-1 mutant animals subjected to heavy metal stress.
Project description:Liquid cultures of the unicellular green alga, Chlamydomonas reinhardtii were grown in media with 6 uM Mn (control) or 1000 uM Mn (experimental), and analyzed by RNA-Seq to identify genes that are differentially expressed in response to excess Mn.
Project description:Recent studies in comparative genomics demonstrate that inter-species comparisons represent a powerful tool for revealing both conserved and specialized biological processes across large evolutionary distances. All cells need to adjust to environmental fluctuations in metal levels since both metal excess and deficit are detrimental. Here, we explore the conservation of metal homoeostasis in two distantly related yeasts, examining genome-wide gene expression responses to changing copper and iron levels in budding and fission yeast using DNA microarrays
Project description:Anthropogenic pollution has increased the levels of heavy metals in the environment. Bacterial populations continue to thrive in highly polluted environments and bacteria must have mechanisms to counter heavy metal stress. We chose to examine the response of the environmentally-relevant organism Pseudomonas aeruginosa to two different copper treatments. A short, 45 min exposure to copper was done in the Cu shock treatment to examine the immediate transcriptional profile to Cu stress. The Cu adapted treatment was designed to view the transcriptional profile of cells that were actively growing in the presence of Cu. Keywords: stress response
Project description:Dunaliella salina Bardawil (also known as Dunaliella bardawil) is an extremophilic, unicellular green alga from the Chlorophyte lineage. D. salina is found in hypersaline environments where it can tolerate extremes of heat, light, pH, and up to saturating concentrations of salt. The D. salina Bardawil isolate (UTEX LB 2538) was found in a salt pond near the Bardawil Lagoon on the Sinai peninsula in 1976. This isolate of D. salina is the richest natural source of beta-carotene, a highly valuable commercial product. This accession includes an RNA-Seq analysis of D. salina Bardawil cultures grown in iron-replete (1.5 µM) or iron-deficient (0 µM) media.