Regulatory RNAs play versatile roles in bacteria in the coordination of gene expression during various physiological processes, especially during stress adaptation. Photosynthetic bacteria use sunlight as their major energy source. Therefore, they are particularly vulnerable to the damaging effects of excess light or UV irradiation. In addition, like all bacteria, photosynthetic bacteria must adapt to limiting nutrient concentrations and abiotic and biotic stress factors. Transcriptome analyses have identified hundreds of potential regulatory small RNAs (sRNAs) in model cyanobacteria such as Synechocystis sp. PCC 6803 or Anabaena sp. PCC 7120, and in environmentally relevant genera such as Trichodesmium, Synechococcus and Prochlorococcus. Some sRNAs have been shown to actually contain μORFs and encode short proteins. Examples include the 40-amino-acid product of the sml0013 gene, which encodes the NdhP subunit of the NDH1 complex. In contrast, the functional characterization of the non-coding sRNA PsrR1 revealed that the 131 nt long sRNA controls photosynthetic functions by targeting multiple mRNAs, providing a paradigm for sRNA functions in photosynthetic bacteria. We suggest that actuatons comprise a new class of genetic elements in which an sRNA gene is inserted upstream of a coding region to modify or enable transcription of that region.

中文翻译：

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光合蓝细菌中的调节RNA。


调节性RNA在细菌中发挥着多种作用，在各种生理过程中协调基因表达，特别是在应激适应过程中。光合细菌利用阳光作为主要能源。因此，它们特别容易受到过量光线或紫外线照射的破坏作用。此外，与所有细菌一样，光合细菌必须适应限制的营养浓度以及非生物和生物胁迫因素。转录组分析已在蓝藻模型（如集胞藻属 sp.）中鉴定出数百种潜在的调节性小 RNA (sRNA)。 PCC 6803 或鱼腥藻 sp。 PCC 7120 以及与环境相关的属，例如 Trichodesmium、Synechococcus 和 ProChlochococcus。一些 sRNA 已被证明实际上含有 μORF 并编码短蛋白质。例子包括 sml0013 基因的 40 个氨基酸产物，它编码 NDH1 复合物的 NdhP 亚基。相比之下，非编码sRNA PsrR1的功能表征表明，131 nt长的sRNA通过靶向多个mRNA来控制光合功能，为光合细菌中的sRNA功能提供了范例。我们认为，驱动器包含一类新的遗传元件，其中 sRNA 基因插入编码区的上游，以修改或启用该区域的转录。