亚端部串联重复序列组成特征对黑麦1R染色体短臂减数分裂识别配对的影响

染色体亚端部串联重复序列会影响其减数分裂的识别和配对。因串联重复序列很难组装，其在染色体亚端部的组成特点不明确，导致其影响同源染色体识别和配对的机制仍不清楚。我们创制了多种黑麦来源的小麦-黑麦1BL.1RS易位系，前期研究已发现不同易位染色体的1RS亚端部的串联重复序列组成有差异，重复序列组成相似的易位染色体具有更高的传递频率。本项目拟继续对1RS亚端部区域的多种串联重复序列家族进行生物信息学分析，设计代表各家族不同类群序列的寡核苷酸探针，借助ND-FISH、GISH和免疫共定位技术，研究不同来源1RS亚端部的串联重复序列组成特征，以及1RS减数分裂识别和配对的动态过程，建立串联重复序列组成特征与同源染色体配对频率之间的联系，明确影响同源染色体识别和配对的重复序列类型。研究结果将初步阐明串联重复序列影响同源染色体识别和配对的机制，也为创制新型小麦-黑麦1BL.1RS易位系提供理论指导。

Tandem repeats in subtelomeric regions of chromosomes can affect recognition and pairing of homologous chromosomes during meiosis. The mechanism is unclear because of the difficulties of assembling tandem repeats resulting in the unclear constitution features of tandem repeats in subtelomeric regions. Several kinds of wheat-rye 1BL.1RS translocation lines, in which 1RS arms were derived from different rye, have been developed. Previous work indicates that the compositions of tandem repeats are different in subtelomeric regions of different 1RS arms, and the 1BL.1RS chromosomes with similar compositions of tandem repeats were easily passed on to offspring. In this project, bioinformatic methods will be used to analyze the monomers of several families of satellite tandem repeats that locate in subtelomeric regions of 1RS arm. Then oligonucleotide probes representing different groups of tandem repeats will be designed. Combined with ND-FISH, GISH and immunolocalization techniques, these oligo probes will be used to investigate the composition feature of tandem repeats on subtelomeric regions of different 1RS arms, to investigate the dynamics of meiotic recognition and pairing of 1RS arms during meiosis, to illuminate the relationship between composition features of tandem repeats and meiotic pairing of 1RS arms, and to illustrate the types of tandem repeats affecting recognition and pairing of homologous chromosomes. The results will preliminarily illustrate the mechanism of tandem repeats affecting recognition and pairing of homologous chromosomes, and provide a theoretical guidance for the development of new wheat-rye 1BL.1RS translocation lines.