Hao Li, Shi Xin, Wen Shiyu, Chen Jiaqiang, Luo Kexin, Chen Yaqi, Yue Samo, Yang Caiye, Sun Yanxia, Zhang Yi
College of Food and Biological Engineering, Chengdu University, Chengdu, 610106, PR China.
Chengdu Institute of Biology, Chinese Academy of Sciences, Chengdu, 610041, PR China.
BMC Genomics. 2024 Dec 3;25(1):1172. doi: 10.1186/s12864-024-11069-5.
Dendrobium officinale Kimura et Migo is a perennial epiphytic herb in traditional Chinese medicine, showing remarkable resistance to salt stress. Water-soluble sugars serve as important osmoprotectants and play crucial roles in plant stress responses. Previous studies have primarily focused on sugar metabolism in individual tissues under stress, resulting in a limited understanding of the regulatory differences between tissues and the relationship between sugar metabolism and transport.
A variety of salt-responsive genes were identified through transcriptome analysis of D. officinale. GO and KEGG enrichment analyses revealed functional differences among the differentially expressed genes (DEGs) between leaves and roots. Expression analysis indicated that sugar metabolic genes and D. officinale Sugars Will Eventually be Exported Transporters (DoSWEETs) displayed distinct expression patterns in leaves and roots under salt stress. Most sugar metabolic genes were up-regulated in the leaves and down-regulated in the roots in response to salt, while DoSWEETs predominantly responded in the roots. Specifically, DoSWEET2a, 6a, 12a, 14, and 16 were confirmed via RT-qPCR. Additionally, positive correlations were observed between certain genes (scrK, INV, SUS) and DoSWEETs, with INV (LOC110096666) showing a strong positive correlation with all detected DoSWEETs in both leaves and roots.
Our findings not only illustrated the distinct responses of leaves and roots to salt stress, but also highlighted the relationship between sugar metabolic genes and DoSWEETs in adapting to such stress. This enhances our understanding of the differential responses of plant tissues to salt stress and identified candidate genes for salt-resistance breeding in D. officinale.
铁皮石斛是一种多年生附生草本植物，在传统中药中具有显著的耐盐胁迫能力。水溶性糖作为重要的渗透保护剂，在植物应激反应中发挥关键作用。以往的研究主要集中在胁迫下单个组织中的糖代谢，导致对组织间调控差异以及糖代谢与转运之间关系的理解有限。
通过对铁皮石斛的转录组分析鉴定出多种盐响应基因。GO和KEGG富集分析揭示了叶片和根之间差异表达基因（DEG）的功能差异。表达分析表明，糖代谢基因和铁皮石斛糖最终输出转运蛋白（DoSWEETs）在盐胁迫下在叶片和根中表现出不同的表达模式。大多数糖代谢基因在盐胁迫下在叶片中上调而在根中下调，而DoSWEETs主要在根中响应。具体而言，通过RT-qPCR证实了DoSWEET2a、6a、12a、14和16。此外，观察到某些基因（scrK、INV、SUS）与DoSWEETs之间存在正相关，其中INV（LOC110096666）在叶片和根中与所有检测到的DoSWEETs均表现出强正相关。
我们的研究结果不仅阐明了叶片和根对盐胁迫的不同响应，还突出了糖代谢基因与DoSWEETs在适应这种胁迫中的关系。这增强了我们对植物组织对盐胁迫差异响应的理解，并确定了铁皮石斛抗盐育种的候选基因。
