Temporal gene expression of the cyanobacterium Arthrospira in response to gamma rays

ABSTRACT: The edible cyanobacterium Arthrospira is highly resistant to ionising radiation. How theses cells can escape, protect or repair the radiation damage is not known, and requires additional molecular investigation. Therefore, in this study, Arthrospira cells were shortly exposed to different doses of 60Co gamma rays and the dynamic response of Arthrospira cells to irradiation was investigated by monitoring its gene expression and cell physiology, after irradiation. The dynamic transcriptome and associated physiological traits showed clearly two events: (1) an intense global emergency response with general reprogramming of carbon and energy metabolism and (2) a recovery period. Genes expressed during early response indicated a reduction of photosynthesis and reduced tricarboxilic acid (TCA) and Calvin Benson Cycles, while a likely activation of pentose phosphate pathway. Activation of biosynthesis of additional carbon storage molecules, compatible solutes, vitamins and sugars transport occurred after irradiation. In addition the cells enhance the restoration of the redox homeostasis. The repair mechanism of Arthrospira cells involve mainly proteases for cellular cleaning and removal of damaged proteins, single strand DNA repair and restriction modification system. During recovery, Arthrospira relies on the powerful antioxidant Glutathione molecule, for ROS detoxification. The exposed cells expressed during recovery period also again highly the arh genes, coding for a group of novel proteins which were detected in our previous irradiation studies, which confirms our hypothesis that they are a key element in the radiation resistance and merit further detailed investigation. This study provides new insights into phasic response and the cellular pathways involved the radiation resistance of microbial cells, in particularly for photosynthetic organisms as the cyanobacterium Arthrospira.

ORGANISM(S): Limnospira indica PCC 8005

PROVIDER: GSE63250 | GEO | 2015/05/31

SECONDARY ACCESSION(S): PRJNA267105

REPOSITORIES: GEO