College of Horticulture, Gansu Agricultural University, Lanzhou, 730000, China.
Northwest Institute of Eco-Environment and Resources, Chinese Academy of Science, Lanzhou, 730000, China.
Mol Genet Genomics. 2018 Dec;293(6):1523-1534. doi: 10.1007/s00438-018-1479-5. Epub 2018 Aug 12.
Iron (Fe) deficiency is a frequent nutritional problem limiting apple production in calcareous soils. The utilization of rootstock that is resistant to Fe deficiency is an effective way to solve this problem. Malus halliana is an Fe deficiency-tolerant rootstock; however, few molecular studies have been conducted on M. halliana. In the present work, a transcriptome analysis was combined with qRT-PCR and sugar measurements to investigate Fe deficiency responses in M. halliana roots at 0 h (T1), 12 h (T2) and 72 h (T3) after Fe deficiency stress. Total of 2473, 661, and 776 differentially expressed genes (DEGs) were identified in the pairs of T2 vs. T1, T3 vs. T1, and T3 vs. T2, respectively. Several DEGs were enriched in the photosynthesis, glycolysis and gluconeogenesis, tyrosine metabolism and fatty acid degradation pathways. The glycolysis and photosynthesis pathways were upregulated under Fe deficiency. In this experiment, sucrose accumulated in Fe-deficient roots and leaves. However, the glucose content significantly decreased in the roots, while the fructose content significantly decreased in the leaves. Additionally, 15 genes related to glycolysis and sugar synthesis and sugar transport were selected to validate the accuracy of the transcriptome data by qRT-PCR. Overall, these results indicated that sugar synthesis and metabolism in the roots were affected by Fe deficiency. Sugar regulation is a way by which M. halliana responds to Fe deficiency stress.
缺铁（Fe）是限制石灰性土壤中苹果生产的常见营养问题。利用对缺铁有抗性的砧木是解决这一问题的有效方法。山荆子是一种耐缺铁的砧木；然而，对山荆子的分子研究很少。本研究采用转录组分析结合 qRT-PCR 和糖测定，研究了缺铁胁迫后 0 h（T1）、12 h（T2）和 72 h（T3）山荆子根对缺铁的反应。在 T2 与 T1、T3 与 T1 和 T3 与 T2 这三对比较中，分别鉴定出 2473、661 和 776 个差异表达基因（DEGs）。几个 DEGs 富集在光合作用、糖酵解和糖异生、酪氨酸代谢和脂肪酸降解途径中。糖酵解和光合作用途径在缺铁条件下被上调。在本实验中，缺铁根和叶中蔗糖积累。然而，根中葡萄糖含量显著下降，而叶中果糖含量显著下降。此外，选择了 15 个与糖酵解和糖合成及糖转运相关的基因，通过 qRT-PCR 验证转录组数据的准确性。总的来说，这些结果表明，根中的糖合成和代谢受到缺铁的影响。糖的调节是山荆子对缺铁胁迫反应的一种方式。
