Data from: Transcriptome analysis of apical meristem enriched bud samples for size dependent flowering commitment in Crocus sativus reveal role of sugar and auxin signalling

Background Cultivation of Crocus sativus (saffron) faces challenges due to inconsistent flowering patterns and variations in yield. Flowering takes place in a graded way with smaller corms unable to produce flowers. Enhancing the productivity requires a comprehensive understanding of the underlying genetic mechanisms that govern this size based flowering initiation and commitment. Therefore, samples enriched with non-flowering and flowering apical buds from small (<6g) and large (>14g) corms were sequenced. Methods and Results Apical bud enriched samples from small and large corms were collected immediately after break of dormancy in July. RNA sequencing was performed using Illumina Novaseq 6000. De-novo transcriptome assembly and analysis using flowering committed buds from large corms at post-dormancy and their comparison with vegetative shoot primordia from small corms pointed out the major role of Auxin and ABA hormonal regulation. Many genes with known dual responses in flowering development and circadian rhythm like Flowering locus T and Cryptochrome 1 along with a transcript showing homology with small auxin upregulated RNA (SAUR) exhibited induced expression in flowering buds. Thorough prediction of Crocus sativus non-coding RNA repertoire has been carried out for the first time. Enolase was found to be acting as a major hub with protein-protein interaction analysis using Arabidopsis counterparts. Conclusion Transcripts belong to key pathways including phenylpropanoid biosynthesis, hormone signaling and carbon metabolism were found significantly modulated. KEGG assessment and protein-protein interaction analysis confirm the expression data. Findings unravel the genetic determinants driving the size-dependent flowering in Crocus sativus.背景 番红花（Crocus sativus，俗称藏红花）的种植面临诸多挑战，其开花模式不稳定且产量波动显著。该植物的开花呈现分级特性：球茎体积较小者无法开花。要提升种植产能，需全面解析调控其球茎大小依赖型开花起始与发育决定过程的潜在遗传机制。为此，研究人员对取自小型（<6g）与大型（>14g）球茎的非开花与开花顶端芽组织富集样本开展了测序。 方法与结果 研究人员于7月休眠刚解除时，采集了小型与大型球茎的顶端芽组织富集样本。采用Illumina Novaseq 6000平台完成RNA测序。通过对大型球茎休眠解除后处于开花决定阶段的芽组织进行从头转录组组装（De-novo transcriptome assembly）与分析，并将其与小型球茎的营养性芽原基进行对比，明确了生长素（Auxin）与脱落酸（ABA）的激素调控在该过程中的核心作用。诸多在开花发育与昼夜节律中已知具有双重功能的基因，如开花位点T（Flowering Locus T）、隐花色素1（Cryptochrome 1），以及一段与生长素上调小RNA（SAUR）同源的转录本，均在开花芽组织中呈现诱导表达模式。本研究首次对番红花的非编码RNA全集进行了全面预测。通过基于拟南芥（Arabidopsis）同源蛋白的蛋白质相互作用分析，发现烯醇化酶（Enolase）是核心互作枢纽。 结论 研究发现，苯丙烷类生物合成、激素信号转导与碳代谢等关键通路的转录本均发生显著调控变化。京都基因与基因组百科全书（KEGG）富集分析与蛋白质相互作用分析验证了转录组表达数据。本研究的发现阐明了调控番红花球茎大小依赖型开花的遗传决定因子。