Tian Meilin, Li Yangping, Jing Jing, Mu Chuang, Du Huixia, Dou Jinzhuang, Mao Junxia, Li Xue, Jiao Wenqian, Wang Yangfan, Hu Xiaoli, Wang Shi, Wang Ruijia, Bao Zhenmin
Ministry of Education Key Laboratory of Marine Genetics and Breeding, College of Marine Life Sciences, Ocean University of China, 5 Yushan Road, Qingdao 266003, China.
Sci Rep. 2015 Oct 6;5:14852. doi: 10.1038/srep14852.
Genetic linkage maps are critical and indispensable tools in a wide range of genetic and genomic research. With the advancement of genotyping-by-sequencing (GBS) methods, the construction of a high-density and high-resolution linkage maps has become achievable in marine organisms lacking sufficient genomic resources, such as echinoderms. In this study, high-density, high-resolution genetic map was constructed for a sea cucumber species, Apostichopus japonicus, utilizing the 2b-restriction site-associated DNA (2b-RAD) method. A total of 7839 markers were anchored to the linkage map with the map coverage of 99.57%, to our knowledge, this is the highest marker density among echinoderm species. QTL mapping and association analysis consistently captured one growth-related QTL located in a 5 cM region of linkage group (LG) 5. An annotated candidate gene, retinoblastoma-binding protein 5 (RbBP5), which has been reported to be an important regulator of cell proliferation, was recognized in the QTL region. This linkage map represents a powerful tool for research involving both fine-scale QTL mapping and marker assisted selection (MAS), and will facilitate chromosome assignment and improve the whole-genome assembly of sea cucumber in the future.
遗传连锁图谱是广泛的遗传和基因组研究中至关重要且不可或缺的工具。随着测序分型（GBS）方法的发展，在缺乏足够基因组资源的海洋生物（如棘皮动物）中构建高密度、高分辨率的连锁图谱已成为可能。在本研究中，利用2b限制性位点相关DNA（2b-RAD）方法为海参物种刺参构建了高密度、高分辨率的遗传图谱。共有7839个标记被锚定到连锁图谱上，图谱覆盖率为99.57%，据我们所知，这是棘皮动物物种中最高的标记密度。数量性状基因座（QTL）定位和关联分析一致捕获到一个位于连锁群（LG）5的5厘摩区域内的与生长相关的QTL。在该QTL区域鉴定出一个注释的候选基因，视网膜母细胞瘤结合蛋白5（RbBP5），据报道它是细胞增殖的重要调节因子。该连锁图谱是涉及精细尺度QTL定位和标记辅助选择（MAS）研究的有力工具，并将有助于未来海参的染色体分配和全基因组组装的改进。
