Identification and function of regulatory RNA in the phototrophic model organism Synechocystis sp. PCC 6803

来自原核生物和真核生物的最新数据显示非编码RNA（ncRNA）作为基因表达的序列特异性调节剂的极高潜力，从而介导对变化的环境线索和形态分化的过多细胞反应。在这里，我们建议解开全套的ncRNA在一个全面和系统的方式，克隆和测序所有的小RNA从蓝藻集胞藻属PCC 6803，通过计算预测ncRNA基因的基因间区域。集胞藻PCC 6803是遗传学研究最好的，也是最容易处理的蓝藻。因此，我们计划利用这些信息，开发这种生物体成为一个真正的模型，用于分析调控RNA在蓝藻中的靶向敲除突变的基因编码的最有前途的ncRNA基因和蛋白质的关键功能的RNA代谢（RNase IM，RNase E，Hfq）。我们将特别强调一个ncRNA的功能分析，这是我们在之前的工作过程中发现的，导致了这一建议。该ncRNA在其全长上与isiA的编码区呈反义方向。在铁限制和氧化还原应激下，isiA的转录水平急剧增加，这种ncRNA参与控制这种增加。

Recent data from pro- and eukaryotic organisms show the extremely high potential of non-coding RNAs (ncRNAs) as sequence-specific regulators of gene expression, thereby mediating a plethora of cellular responses to changing environmental clues, and morphological differentiation. Here, we suggest to unravel the full set of ncRNAs in a comprehensive and systematical way by cloning and sequencing all small RNAs from the cyanobacterium Synechocystis sp. PCC 6803, paralleled by a computational prediction of ncRNA genes in intergenic regions. Synechocystis sp. PCC 6803 is the genetically best studied and easiest to handle cyanobacterium. We therefore plan to use this information to develop this organism into a true model for the analysis of regulatory RNAs in cyanobacteria by targeted knock-out mutations of genes encoding the most promising ncRNA genes and proteins with key functions in the metabolism of RNA (RNase IM, RNase E, Hfq). We will put special emphasis on the functional analysis of one ncRNA, which we have identified in the course of prior work that has led to this proposal. This ncRNA is over its full length in antisense orientation to the coding region of isiA. Transcript levels for isiA increase sharply under iron limitation and redox stress and this ncRNA is involved in the control of this increase.