Saccharum hybrid cultivar Raw sequence reads

Sugarcane smut caused by Sporisorium scitamineum is a critical fungal disease in the sugarcane industry. However, molecular mechanistic studies of pathological response of sugarcane to S. scitamineum are scarce and preliminary. Here, transcriptome analysis of sugarcane disease induced by S. scitamineum at 24, 48 and 120 h was conducted, using an S. scitamineum-resistant and -susceptible genotype (Yacheng05-179 and ''ROC''22). The reliability of Illumina data was confirmed by real-time quantitative PCR. In total, transcriptome sequencing of eight samples revealed gene annotations of 65,852 unigenes. Correlation analysis of differentially expressed genes indicated that after S. scitamineum infection, most differentially expressed genes and related metabolic pathways in both sugarcane genotypes were common, covering most biological activities. However, expression of resistance-associated genes in Yacheng05-179 (24–48 h) occurred earlier than those in ''ROC''22 (48–120 h), and more transcript expressions were observed in the former, suggesting resistance specificity and early timing of these genes in non-affinity sugarcane and S. scitamineum interactions. Obtained unigenes were related to cellular components, molecular functions and biological processes. From these data, functional annotations associated with resistance were obtained, including signal transduction mechanisms, energy production and conversion, inorganic ion transport and metabolism, and defense mechanisms. Pathway enrichment analysis revealed that differentially expressed genes are involved in plant hormone signal transduction, flavonoid biosynthesis, plant-pathogen interaction, cell wall fortification pathway and other resistance-associated metabolic pathways. In conclusion, expression data here represent the most comprehensive dataset available for sugarcane smut induced by S. scitamineum and will serve as a resource for finally unraveling the molecular mechanisms of sugarcane responses to S. scitamineum.

由甘蔗黑粉菌（Sporisorium scitamineum）引发的甘蔗黑穗病，是制约甘蔗产业发展的重大真菌病害。然而，当前针对甘蔗响应甘蔗黑粉菌的病理分子机制研究仍较为匮乏且初步。本研究以抗甘蔗黑粉菌基因型Yacheng05-179与感病基因型'ROC'22为材料，对接种病原菌后24、48及120小时的甘蔗样本进行转录组分析。通过实时定量PCR（real-time quantitative PCR）验证了Illumina测序数据的可靠性。本次转录组测序共涵盖8个样本，最终获得65852个单基因（unigene）的基因注释信息。差异表达基因相关性分析结果表明，接种甘蔗黑粉菌后，两个甘蔗基因型中共有的差异表达基因及相关代谢通路占多数，覆盖了绝大多数生物学活动过程。但相较于感病品种'ROC'22（基因表达响应窗口为48~120 h），抗病品种Yacheng05-179的抗病相关基因表达更早（响应窗口为24~48 h），且其差异转录本的表达量更高，提示在甘蔗与甘蔗黑粉菌的非亲和互作体系中，抗病相关基因具有应答特异性与时序超前性。所鉴定的单基因功能注释涵盖细胞组分、分子功能与生物学过程三大功能类别。基于上述数据，我们筛选得到与抗病性相关的功能注释模块，包括信号转导机制、能量产生与转化、无机离子转运与代谢以及防御机制等。通路富集分析显示，差异表达基因参与了植物激素信号转导、黄酮类生物合成、植物-病原互作、细胞壁强化通路等多种抗病相关代谢通路。综上，本研究获得的表达谱数据集是目前针对甘蔗黑粉菌诱导甘蔗免疫应答的最为全面的公开数据资源，可为最终解析甘蔗响应甘蔗黑粉菌的分子机制提供关键支撑。