Liu Na, Zhang Guwen, Xu Shengchun, Mao Weihua, Hu Qizan, Gong Yaming
Institute of Vegetables, Zhejiang Academy of Agricultural Sciences Hangzhou, China.
Center of Analysis and Measurement, Zhejiang University Hangzhou, China.
Front Plant Sci. 2015 Nov 25;6:1039. doi: 10.3389/fpls.2015.01039. eCollection 2015.
Understanding the molecular mechanisms regulating pea seed developmental process is extremely important for pea breeding. In this study, we used high-throughput RNA-Seq and bioinformatics analyses to examine the changes in gene expression during seed development in vegetable pea and grain pea, and compare the gene expression profiles of these two pea types. RNA-Seq generated 18.7 G of raw data, which were then de novo assembled into 77,273 unigenes with a mean length of 930 bp. Our results illustrate that transcriptional control during pea seed development is a highly coordinated process. There were 459 and 801 genes differentially expressed at early and late seed maturation stages between vegetable pea and grain pea, respectively. Soluble sugar and starch metabolism related genes were significantly activated during the development of pea seeds coinciding with the onset of accumulation of sugar and starch in the seeds. A comparative analysis of genes involved in sugar and starch biosynthesis in vegetable pea (high seed soluble sugar and low starch) and grain pea (high seed starch and low soluble sugar) revealed that differential expression of related genes at late development stages results in a negative correlation between soluble sugar and starch biosynthetic flux in vegetable and grain pea seeds. RNA-Seq data was validated by using real-time quantitative RT-PCR analysis for 30 randomly selected genes. To our knowledge, this work represents the first report of seed development transcriptomics in pea. The obtained results provide a foundation to support future efforts to unravel the underlying mechanisms that control the developmental biology of pea seeds, and serve as a valuable resource for improving pea breeding.
了解调控豌豆种子发育过程的分子机制对豌豆育种极为重要。在本研究中，我们利用高通量RNA测序和生物信息学分析来检测蔬菜豌豆和籽粒豌豆种子发育过程中的基因表达变化，并比较这两种豌豆类型的基因表达谱。RNA测序产生了18.7 G的原始数据，然后将其从头组装成77,273个单基因，平均长度为930 bp。我们的结果表明，豌豆种子发育过程中的转录调控是一个高度协调的过程。蔬菜豌豆和籽粒豌豆在种子成熟早期和晚期分别有459个和801个基因差异表达。与可溶性糖和淀粉代谢相关的基因在豌豆种子发育过程中显著激活，这与种子中糖和淀粉积累的开始相一致。对蔬菜豌豆（种子可溶性糖含量高，淀粉含量低）和籽粒豌豆（种子淀粉含量高，可溶性糖含量低）中参与糖和淀粉生物合成的基因进行比较分析发现，发育后期相关基因的差异表达导致蔬菜豌豆和籽粒豌豆种子中可溶性糖和淀粉生物合成通量呈负相关。通过对30个随机选择的基因进行实时定量RT-PCR分析验证了RNA测序数据。据我们所知，这项工作是豌豆种子发育转录组学的首次报道。所获得的结果为支持未来揭示控制豌豆种子发育生物学潜在机制的努力提供了基础，并为改进豌豆育种提供了宝贵资源。
