Pan Yiling, Luo Yujia, Bao Jingkai, Wu Cuiyun, Wang Jiurui, Liu Mengjun, Yan Fenfen
College of Horticulture and Forestry, Tarim University/The National-Local Joint Engineering Laboratory of High Efficiency and Superior-Quality Cultivation and Fruit Deep Processing Technology on Characteristic Fruit Trees, Xinjiang, Alar, China.
College of Forestry, Hebei Agricultural University, Baoding, China.
Front Plant Sci. 2024 Apr 2;15:1361771. doi: 10.3389/fpls.2024.1361771. eCollection 2024.
Fruit size is an important economic trait affecting jujube fruit quality, which has always been the focus of marker-assisted breeding of jujube traits. However, despite a large number of studies have been carried out, the mechanism and key genes regulating jujube fruit size are mostly unknown.
In this study, we used a new analysis method Quantitative Trait Loci sequencing (QTL-seq) (bulked segregant analysis) to screen the parents 'Yuhong' and 'Jiaocheng 5' with significant phenotypic differences and mixed offspring group with extreme traits of large fruit and small fruit, respectively, and, then, DNA mixed pool sequencing was carried out to further shortening the QTL candidate interval for fruit size trait and excavated candidate genes for controlling fruit size.
The candidate intervals related to jujube fruit size were mainly located on chromosomes 1, 5, and 10, and the frequency of chromosome 1 was the highest. Based on the QTL-seq results, the annotation results of ANNOVAR were extracted from 424 SNPs (single-nucleotide polymorphisms) and 164 InDels (insertion-deletion), from which 40 candidate genes were selected, and 37 annotated candidate genes were found in the jujube genome. Four genes (, , , and ) that are associated with fruit size growth and development were identified by functional annotation of the genes in NCBI (National Center for Biotechnology Information). The genes can provide a basis for further exploration and identification on genes regulating jujube fruit size.
In summary, the data obtained in this study revealed that QTL intervals and candidate genes for fruit size at the genomic level provide valuable resources for future functional studies and jujube breeding.
果实大小是影响枣果实品质的重要经济性状，一直是枣性状分子标记辅助育种的重点。然而，尽管已经开展了大量研究，但调控枣果实大小的机制和关键基因大多仍不清楚。
本研究采用一种新的分析方法——数量性状位点测序（QTL-seq）（混合分组分析法），筛选出表型差异显著的亲本‘豫红’和‘交城5号’，并分别构建了具有大果和小果极端性状的后代混合群体，然后进行DNA混合池测序，以进一步缩短果实大小性状的QTL候选区间，并挖掘控制果实大小的候选基因。
与枣果实大小相关的候选区间主要位于第1、5和10号染色体上，其中第1号染色体上出现的频率最高。基于QTL-seq结果，从424个单核苷酸多态性（SNP）和164个插入缺失（InDel）中提取ANNOVAR的注释结果，从中筛选出40个候选基因，在枣基因组中发现了37个有注释的候选基因。通过美国国立生物技术信息中心（NCBI）对这些基因的功能注释，鉴定出4个与果实大小生长发育相关的基因（、、和）。这些基因为进一步探索和鉴定调控枣果实大小的基因提供了依据。
综上所述，本研究获得的数据表明，基因组水平上果实大小的QTL区间和候选基因为未来的功能研究和枣育种提供了有价值的资源。
