Transcriptome analysis of thermoplasma volcanium GSS1 under extreme stress

Zabcı, Sema
In this study, to provide new insight into anti-stress mechanisms in archaea, we have carried out genome wide transcriptome analysis of Thermoplasma volcanium under severe stress conditions (i.e., heat- shock at 68 ºC, sub-lethal and lethal oxidative stress and pH stress at pH 5.0) using whole genome gene expression microarray. The change in the gene expression profile in response to three stressors indicated retardation of cell growth accompanied by down regulation of genes involved in essential cellular processes such as translation, transcription, cell motility, and energy metabolism. In addition, heat- shock resulted in the increased transcription level of genes encoding heat shock proteins (e.g., GroEL, GrpE, DnaK, and DnaJ). The highest number of up-regulated genes was recorded upon pH stress. pH stress response in T.volcanium was characterized by activation of several transporter gene products, which are crucial for maintaining intracellular pH homeostasis. Oxidative stress triggered mostly down regulation of gene expression. Up regulation of oxidoreductases, Fe-S oxidoreductases, aldo/keto reductases, and dehydrogenases as a response to oxidative stress provoked by H2O2 can be important for maintaining intracellular redox potential and detoxification of free radicals. On the other hand, activation of the carbohydrate metabolism and transport, as well as some transcriptional regulators was detected in response to three stress signals. The verification of the microarray data with qRT-PCR showed good agreement between results of the two techniques
Citation Formats
S. Zabcı, “Transcriptome analysis of thermoplasma volcanium GSS1 under extreme stress,” M.S. - Master of Science, Middle East Technical University, 2015.