Li Shu-Fen, Zhang Guo-Jun, Zhang Xue-Jin, Yuan Jin-Hong, Deng Chuan-Liang, Gao Wu-Jun
College of Life Sciences, Henan Normal University, Xinxiang, 453007, China.
School of Basic Medical Sciences, Xinxiang Medical University, Xinxiang, 453003, China.
BMC Plant Biol. 2017 Aug 22;17(1):143. doi: 10.1186/s12870-017-1091-6.
Garden asparagus (Asparagus officinalis) is a highly valuable vegetable crop of commercial and nutritional interest. It is also commonly used to investigate the mechanisms of sex determination and differentiation in plants. However, the sex expression mechanisms in asparagus remain poorly understood.
De novo transcriptome sequencing via Illumina paired-end sequencing revealed more than 26 billion bases of high-quality sequence data from male and female asparagus flower buds. A total of 72,626 unigenes with an average length of 979 bp were assembled. In comparative transcriptome analysis, 4876 differentially expressed genes (DEGs) were identified in the possible sex-determining stage of female and male/supermale flower buds. Of these DEGs, 433, including 285 male/supermale-biased and 149 female-biased genes, were annotated as flower related. Of the male/supermale-biased flower-related genes, 102 were probably involved in anther development. In addition, 43 DEGs implicated in hormone response and biosynthesis putatively associated with sex expression and reproduction were discovered. Moreover, 128 transcription factor (TF)-related genes belonging to various families were found to be differentially expressed, and this finding implied the essential roles of TF in sex determination or differentiation in asparagus. Correlation analysis indicated that miRNA-DEG pairs were also implicated in asparagus sexual development.
Our study identified a large number of DEGs involved in the sex expression and reproduction of asparagus, including known genes participating in plant reproduction, plant hormone signaling, TF encoding, and genes with unclear functions. We also found that miRNAs might be involved in the sex differentiation process. Our study could provide a valuable basis for further investigations on the regulatory networks of sex determination and differentiation in asparagus and facilitate further genetic and genomic studies on this dioecious species.
芦笋（石刁柏）是一种具有重要商业价值和营养价值的蔬菜作物。它也常用于研究植物性别决定和分化的机制。然而，芦笋的性别表达机制仍知之甚少。
通过Illumina双末端测序进行的从头转录组测序揭示了来自雄性和雌性芦笋花芽的超过260亿个高质量序列数据碱基。共组装了72626个单基因，平均长度为979 bp。在比较转录组分析中，在雌性和雄性/超雄花芽可能的性别决定阶段鉴定出4876个差异表达基因（DEG）。在这些DEG中，有433个被注释为与花相关，其中包括285个雄性/超雄偏向基因和149个雌性偏向基因。在雄性/超雄偏向的花相关基因中，有102个可能参与花药发育。此外，还发现了43个与激素反应和生物合成相关的DEG，推测它们与性别表达和繁殖有关。此外，发现属于不同家族的128个转录因子（TF）相关基因差异表达，这一发现暗示了TF在芦笋性别决定或分化中的重要作用。相关性分析表明，miRNA-DEG对也与芦笋的性发育有关。
我们的研究鉴定出大量参与芦笋性别表达和繁殖的DEG，包括参与植物繁殖、植物激素信号传导、TF编码的已知基因以及功能不明的基因。我们还发现miRNA可能参与性别分化过程。我们的研究可为进一步研究芦笋性别决定和分化的调控网络提供有价值的基础，并促进对这种雌雄异株物种的进一步遗传和基因组研究。
