Data from: High throughput sequencing of small RNAs reveals dynamic microRNAs expression of lipid metabolism during Camellia oleifera and C. meiocarpa seed natural drying

AbstractBackground: Camellia species are ancient oilseed plants with a history of cultivation over two thousand years. Prior to oil extraction, natural seed drying is often practiced, a process affecting fatty acid quality and quantity. MicroRNAs (miRNA) of lipid metabolism associated with camellia seed natural drying are unexplored. To obtain insight into the function of miRNAs in lipid metabolism during natural drying, Illumina sequencing of C. oleifera and C. meiocarpa small-RNA was conducted. Results: A total of 274 candidate miRNAs were identified and 3733 target unigenes were annotated by performing a BLASTX. Through integrated GO and KEGG function annotation, 23 miRNA regulating 131 target genes were identified as lipid metabolism, regulating fatty acid biosynthesis, accumulation and catabolism. We observed one, two, and four miRNAs of lipid metabolism which were specially expressed in C. Meiocarpa, C. oleifera, and the two species collectively, respectively. At 30% moisture contents, C. meiocarpa and C. oleifer produced nine and eight significant differentially expressed miRNAs, respectively, with high fatty acid synthesis and accumulation activities. Across the two species, 12 significant differentially expressed miRNAs were identified at the 50% moisture content. Conclusions: Sequencing of small-RNA revealed the presence of 23 miRNAs regulating lipid metabolism in camellia seed during natural drying and permitted comparative miRNA profiles between C. Meiocarpa and C. oleifera. Furthermore, this study successfully identified the best drying environment at which the quantity and quality of lipid in camellia seed are at its maximum., Usage notessequence of miRNAs of camellia species in seed natural drying processCamellia miRNAs related to lipid metabolism摘要与背景：山茶属（Camellia）植物是一类拥有两千余年栽培历史的古老油料作物。在油脂提取前，通常会对种子进行自然干燥处理，该过程会直接影响脂肪酸的品质与含量。目前，与山茶籽自然干燥过程相关的脂质代谢微小RNA（miRNA）研究仍处于空白。为深入探究自然干燥阶段miRNA在脂质代谢中的调控功能，本研究对油茶（Camellia oleifera, C. oleifera）和小果油茶（Camellia meiocarpa, C. meiocarpa）的小RNA开展了Illumina高通量测序。 研究结果：本研究共鉴定出274个候选miRNA，并通过BLASTX注释得到3733个靶单基因转录本（unigene）。通过整合基因本体（Gene Ontology, GO）与京都基因与基因组百科全书（Kyoto Encyclopedia of Genes and Genomes, KEGG）功能注释，最终筛选出23个miRNA，其调控的131个靶基因参与脂质代谢过程，涵盖脂肪酸的生物合成、积累与分解代谢。研究发现，分别有1个、2个、4个脂质代谢相关miRNA仅在小果油茶、油茶以及两个物种中共同表达。当种子含水率为30%时，小果油茶与油茶分别出现9个和8个显著差异表达miRNA，此时二者均表现出较高的脂肪酸合成与积累活性。在含水率为50%时，两个物种共鉴定出12个显著差异表达miRNA。 研究结论：小RNA测序结果揭示了23个参与山茶籽自然干燥过程中脂质代谢调控的miRNA，并实现了小果油茶与油茶的miRNA表达谱对比分析。此外，本研究成功确定了可使山茶籽脂质含量与品质达到最优的干燥环境条件。 使用说明：山茶属植物种子自然干燥过程中的miRNA序列；脂质代谢相关山茶miRNA