Identifying genes involved in microRNA turnover in Arabidopsis

MicroRNAs （miRNAs）是一种小的非编码RNA分子，通过靶向mrna调节蛋白质编码基因的表达。由于mirna在发育和对生物和非生物胁迫的反应中起着关键作用，因此在正确的时间和地点表达mirna非常重要。因此，必须有一种降解miRNA （miRNA周转）的机制，并且必须仔细调节该机制本身，以确保miRNA在不需要其功能时不存在。然而，我们对这一机制及其调控知之甚少。成功的候选人将进行突变筛选，以确定参与miRNA转换的基因。筛选试验依赖于GFP传感器，该传感器被miRNA靶向。miRNA的表达将通过在特殊培养基上萌发种子来诱导。改变培养基后，miRNA转录被关闭，现有的miRNA分子被降解，导致幼苗中绿色荧光恢复。成功的候选人将筛选显示更快或更慢的GFP恢复的行。在验证突变表型后，学生将通过下一代测序识别突变基因。鉴定参与miRNA转换的基因将为RNA沉默领域开辟一个新的领域。了解这些基因的功能以及miRNA转换是如何被调节的，将影响植物生物学的各个方面，也将影响生物医学，因为sirna是潜在的治疗药物。

MicroRNAs (miRNAs) are small non-coding RNA molecules regulating the expression of protein coding genes by targeting mRNAs. Since they play key roles in development and in responses to both biotic and abiotic stresses, it is important that miRNAs are expressed at the right time and place. Therefore there must be a mechanism to degrade miRNAs (miRNA turnover) and that mechanism itself must be carefully regulated to ensure that miRNAs are not present when their function is not required. However, we know very little about this mechanism and its regulation. The successful candidate will carry out a mutant screen to identify genes involved in miRNA turnover. The screening assay relies on a GFP sensor, which is targeted by a miRNA. Expression of the miRNA will be induced by germinating seeds on a special media. After changing the media the miRNA transcription is switched off and the existing miRNA molecules will be degraded, leading to green fluorescence recovery in the seedlings. The successful candidate will screen for lines exhibiting faster or slower GFP recovery. After validation of the mutant phenotype the student will identify the mutant genes by next generation sequencing. Identifying genes involved in miRNA turnover will open up a new field in the RNA silencing area. Understanding the function of those genes and how miRNA turnover is regulated will impact on all aspect of plant biology but also on biomedicine as siRNAs are potential therapeutics.