Key Laboratory of Agricultural Ecology and Environment, College of Forestry, Shandong Agricultural University, Tai'an, Shandong 271018, PR China; Silviculture Key Lab of Shandong Province Forestry, College of Shandong Agricultural University, Tai'an, Shandong 271018, PR China.
Key Laboratory of Agricultural Ecology and Environment, College of Forestry, Shandong Agricultural University, Tai'an, Shandong 271018, PR China; Silviculture Key Lab of Shandong Province Forestry, College of Shandong Agricultural University, Tai'an, Shandong 271018, PR China.
Genomics. 2019 Jul;111(4):700-709. doi: 10.1016/j.ygeno.2018.04.007. Epub 2018 Apr 14.
Branching in woody plants affects their ecological benefits and impacts wood formation. To obtain genome-wide insights into the transcriptome changes and regulatory mechanisms associated with branching, we performed high-throughput RNA sequencing to characterize cDNA libraries generated from active buds of Populus deltoides CL. 'zhonglin2025' (BC) and Populus × zhaiguanheibaiyang (NC). NC has more branches than BC and rapid growth. We obtained a total of 198.2 million high-quality clean reads from the NC and BC libraries. We detected 3543 differentially expressed genes (DEGs) between the NC and BC libraries; 1418 were down-regulated and 2125 were up-regulated. Gene ontology functional classification of the DEGs indicated that they included 89 genes that encoded proteins related to hormone biosynthesis, 364 genes related to hormone signaling transduction, and 104 related to the auxin efflux transmembrane transporter. We validated the expression profiles of 16° by real-time quantitative PCR and found that their expression patterns were similar to those obtained from the high-throughput RNA sequencing data. We also measured the hormone content in young buds of BC and NC by high-pressure liquid chromatography. In this study, we identified global hormone regulatory patterns and differences in gene expression between NC and BC, and constructed a hormone regulatory network to explain branching in Populus buds. In addition, candidate genes that may be useful for molecular breeding of particular plant types were identified. Our results will provide a starting point for future investigations into the molecular mechanisms of branching in Populus.
树木分枝会影响其生态效益和木材形成。为了全面了解与分枝相关的转录组变化和调控机制，我们对来自活力旺盛的银腺杨（BC）和中林 2025（NC）的芽 cDNA 文库进行了高通量 RNA 测序。NC 的分枝比 BC 多，生长速度也更快。我们从 NC 和 BC 文库中共获得了 1.982 亿个高质量清洁读数。我们在 NC 和 BC 文库中检测到 3543 个差异表达基因（DEGs）；其中 1418 个下调，2125 个上调。对 DEGs 的基因本体功能分类表明，它们包括 89 个编码与激素生物合成相关蛋白的基因、364 个与激素信号转导相关的基因和 104 个与生长素外排跨膜转运蛋白相关的基因。我们通过实时定量 PCR 对 16 个基因的表达谱进行了验证，发现它们的表达模式与高通量 RNA 测序数据相似。我们还通过高效液相色谱法测量了 BC 和 NC 幼芽中的激素含量。在这项研究中，我们确定了 NC 和 BC 之间的全局激素调控模式和基因表达差异，并构建了一个激素调控网络，以解释杨芽的分枝。此外，还鉴定了可能对特定植物类型的分子育种有用的候选基因。我们的研究结果将为进一步研究杨树分枝的分子机制提供起点。
