Key Laboratory of Biotechnology and Bioresources Utilization, Ministry of Education, Institute of Plant Resources, Dalian Minzu University, Dalian, 116600, China.
Institute of Berries, Heilongjiang Academy of Agricultural Sciences, Suiling, 152200, China.
Sci Rep. 2018 Mar 5;8(1):4022. doi: 10.1038/s41598-018-22464-w.
Sea buckthorn is a plant of medicinal and nutritional importance owing in part to the high levels of essential fatty acids, linoleic (up to 42%) and α-linolenic (up to 39%) acids in the seed oil. Sea buckthorn can produce seeds either via the sexual pathway or by apomixis. The seed development and maturation programs are critically dependent on miRNAs. To understand miRNA-mediated regulation of sea buckthorn seed development, eight small RNA libraries were constructed for deep sequencing from developing seeds of a low oil content line 'SJ1' and a high oil content line 'XE3'. High-throughput sequencing identified 137 known miRNA from 27 families and 264 novel miRNAs. The potential targets of the identified miRNAs were predicted based on sequence homology. Nineteen (four known and 15 novel) and 22 (six known and 16 novel) miRNAs were found to be involved in lipid biosynthesis and seed size, respectively. An integrated analysis of mRNA and miRNA transcriptome and qRT-PCR identified some key miRNAs and their targets (miR164d-ARF2, miR168b-Δ9D, novelmiRNA-108-ACC, novelmiRNA-23-GPD1, novelmiRNA-58-DGAT1, and novelmiRNA-191-DGAT2) potentially involved in seed size and lipid biosynthesis of sea buckthorn seed. These results indicate the potential importance of miRNAs in regulating lipid biosynthesis and seed size in sea buckthorn.
沙棘是一种具有药用和营养价值的植物，部分原因是其籽油中含有高水平的必需脂肪酸，亚油酸（高达 42%）和α-亚麻酸（高达 39%）。沙棘可以通过有性途径或无融合生殖产生种子。种子的发育和成熟程序严重依赖于 miRNAs。为了了解 miRNA 介导的沙棘种子发育调控，我们从低油含量的 SJ1 品系和高油含量的 XE3 品系的发育种子中构建了 8 个小 RNA 文库进行深度测序。高通量测序从 27 个家族中鉴定出了 137 个已知的 miRNA 和 264 个新的 miRNA。根据序列同源性预测了鉴定出的 miRNA 的潜在靶标。发现 19 个（4 个已知和 15 个新）和 22 个（6 个已知和 16 个新）miRNA 分别参与脂质生物合成和种子大小。miRNA 转录组和 qRT-PCR 的综合分析鉴定出了一些关键的 miRNA 和它们的靶标（miR164d-ARF2、miR168b-Δ9D、novelmiRNA-108-ACC、novelmiRNA-23-GPD1、novelmiRNA-58-DGAT1 和 novelmiRNA-191-DGAT2），它们可能参与沙棘种子的大小和脂质生物合成。这些结果表明，miRNAs 在调节沙棘种子的脂质生物合成和种子大小方面具有潜在的重要性。
