Identification and functional characterization of genes involved in the process of root-specific B chromosome elimination in Aegilops speltoides

生物体的所有细胞不一定都含有相同的基因组。一些真核生物在不同器官的细胞之间表现出显着的基因组差异，这是由于染色体或其片段的程序性消除。以山羊草Aegilops speltoides（2n = 2x = 14）为模型，证明了B染色体的消除是一个严格控制的高效根特异性过程。超数B染色体是真菌、植物和动物中存在的一种染色体组元件。在以前的研究中，我们表明，根限制消除Bs开始与胚根形成在胚胎分化的发病，并通过微核发生。这可能是由于姐妹染色单体凝聚力延长导致的不分离。但B染色体消除的分子机制仍不清楚。在应用项目的框架内，对这一现象进行了深入的描述，旨在确定控制消除过程的转录本。具有和不具有Bs的胚的转录组将与在单子叶植物物种中控制染色体消除的解密转录物/基因进行比较。将使用病毒诱导的基因沉默（VIGS）方法对候选基因进行功能评价

Not necessarily all cells of an organism contain the same genome. Some eukaryotes exhibit dramatic genomic differences between cells of different organs, resulting from programmed elimination of chromosomes or their fragments. Using the goatgrass Aegilops speltoides (2n = 2x = 14) as a model, we demonstrated that the elimination of B chromosomes is a strictly controlled and a highly efficient root-specific process. Supernumerary B chromosomes (Bs) are dispensable genomic elements found in fungi, plants and animals. In a previous study we showed that the root-restricted elimination of Bs starts with radicle formation at the onset of embryo differentiation and occurs via micronucleation. It is likely caused by nondisjunction due to prolonged sister-chromatid cohesion. But the molecular mechanism underlying B chromosome elimination remains unknown. In frame of the applied project an in-depth characterization of this phenomenon is aimed to identify transcripts controlling the process of elimination. The transcriptomes of embryos with and without Bs will be compared to decipher transcripts/genes controlling chromosome elimination in a monocot species. Candidate genes will be functionally evaluated using a virus-induced gene silencing (VIGS) approach