Katoh Hiroshi
Mie University, Mie, Japan.
Biochim Biophys Acta. 2012 Aug;1817(8):1263-9. doi: 10.1016/j.bbabio.2012.03.029. Epub 2012 Apr 1.
Terrestrial cyanobacteria have various desiccation-tolerant systems, which are controlled by desiccation tolerance-related genes. Anabaena (Nostoc) sp. strain PCC 7120 is a derivative of the terrestrial cyanobacterium Nostoc and is a useful strain for molecular biological analysis. To identify desiccation tolerance-related genes, we selected and disrupted various genes (all0801, all0875, alr3090, alr3800, all4052, all4477, and alr5182) and examined their gene expression patterns and predicted their functions. Analyses of gene disruptants showed that viability of the disruptants only decreased under N(2)-fixing conditions during desiccation, and the decrease in viability was negatively correlated with the gene expression pattern during desiccation. These data suggest that terrestrial cyanobacteria may acclimate to desiccation stress via N(2) fixation by using desiccation inducible genes, which are not only related to nitrogen fixation or nitrogen metabolism but also to other systems such as metabolism, transcription, and protein repair for protection against desiccation damage under nitrogen-fixing conditions. Further, a photosynthetic gene is required for desiccation tolerance. This article is part of a Special Issue entitled: Photosynthesis Research for Sustainability: from Natural to Artificial.
陆生蓝细菌具有多种耐旱系统，这些系统由耐旱相关基因控制。鱼腥藻（念珠藻）属PCC 7120菌株是陆生蓝细菌念珠藻的一个衍生物，是用于分子生物学分析的有用菌株。为了鉴定耐旱相关基因，我们选择并破坏了各种基因（all0801、all0875、alr3090、alr3800、all4052、all4477和alr5182），并检测了它们的基因表达模式并预测了其功能。对基因破坏突变体的分析表明，仅在干燥过程中的固氮条件下，破坏突变体的活力才会下降，并且活力的下降与干燥过程中的基因表达模式呈负相关。这些数据表明，陆生蓝细菌可能通过利用干燥诱导基因进行固氮来适应干燥胁迫，这些基因不仅与固氮或氮代谢有关，还与其他系统如代谢、转录和蛋白质修复有关，以在固氮条件下保护细胞免受干燥损伤。此外，耐旱性需要一个光合基因。本文是名为：可持续性光合作用研究：从自然到人工的特刊的一部分。
