Food Safety Research Center, Hebei North University, Zhangjiakou, 075000, China.
Heibei Key Laboratory of Quality and Safety Analysis-Testing for Agro-products and Food, Hebei North University, Zhangjiakou, 075000, China.
Genes Genomics. 2019 Dec;41(12):1505-1516. doi: 10.1007/s13258-019-00871-1. Epub 2019 Oct 5.
To study the essential molecular mechanism of gall formation is very important.
To investigate the differential gene expression in leaves fed on by Tetraneura akinire Sasaki and to provide a basis for the better understanding of the essential molecular mechanism of gall formation.
The infected leaves of the elm were divided into three periods: initial formation period (T2), growth and differentiation period (T3), and cracking period (T4). The untouched leaves were used as the control (T1). RNA-Seq was performed, and the high-quality sequences were mapped to the reference genome and the elm gene database to obtain the gene expression profiles. The expression level of each gene was calculated by the RPKM method. A combination of FDR ≤ 0.01 and the absolute value of |log2 ratio (T/CK)| ≥ 2 was used as the threshold to determine the significance of gene expression. Finally, GO and pathway enrichment analyses were used to identify the significantly enriched functional classification and metabolic pathways in DEGs.
The results revealed that approximately 244 mRNAs were detected between T1 and T2, including 192 up-regulated and 52 down-regulated mRNAs; approximately 175 mRNAs were detected between T1 and T3, including 145 up-regulated and 30 down-regulated mRNAs; and approximately 372 mRNAs were detected between T1 and T4, including 360 up-regulated and 12 down-regulated mRNAs. Approximately 34 differentially expressed genes were identified by Venn analysis. Comparing the three infection periods to the control, there were 28 up-regulated and six down-regulated mRNAs. Additionally, 562 genes were used for cluster analysis, which revealed that the gene expression in T2 and T3 changed greatly. Genes related to cell proliferation and respiration, such as microtubulin and 6-phosphoric acid fructose kinase were mainly up-regulated during the T2 period. Genes encoding lipoxygenase, glutathione-S-transferase, superoxide dismutase and protease inhibitor were up-regulated during T2 and T3. Genes encoding lignocellulose synthase were up-regulated during T4, which suggests the reinforcement of the cell wall to improve the resistance to the damage of the Tetraneura akinire Sasaki.
The results showed that the feeding of Tetraneura akinire Sasaki caused the differential expression of elm genes and influenced cellular energy metabolism. These changes in physiological response and gene expression of the elm compose the physiological and molecular basis of the gall formation and may improve the resistance of elm to Tetraneura akinire Sasaki.
研究胆形成的基本分子机制非常重要。
研究受榆绿毛萤叶甲取食的叶片中的差异表达基因，为更好地理解胆形成的基本分子机制提供依据。
将榆叶片分为初始形成期（T2）、生长分化期（T3）和开裂期（T4）三个时期，未受取食的叶片作为对照（T1）。进行 RNA-Seq，将高质量序列映射到参考基因组和榆基因数据库，获得基因表达谱。用 RPKM 法计算每个基因的表达水平。以 FDR≤0.01 和|log2 比值（T/CK）|≥2 的绝对值为阈值，确定基因表达的显著性。最后，用 GO 和通路富集分析鉴定 DEGs 中显著富集的功能分类和代谢途径。
结果表明，T1 和 T2 之间检测到约 244 个 mRNAs，包括 192 个上调和 52 个下调 mRNAs；T1 和 T3 之间检测到约 175 个 mRNAs，包括 145 个上调和 30 个下调 mRNAs；T1 和 T4 之间检测到约 372 个 mRNAs，包括 360 个上调和 12 个下调 mRNAs。通过 Venn 分析鉴定了约 34 个差异表达基因。将三个感染期与对照相比，有 28 个上调和 6 个下调 mRNAs。此外，对 562 个基因进行聚类分析，结果表明 T2 和 T3 期的基因表达变化较大。T2 期主要上调与细胞增殖和呼吸有关的微管蛋白和 6-磷酸果糖激酶等基因，T2 和 T3 期上调与脂氧合酶、谷胱甘肽-S-转移酶、超氧化物歧化酶和蛋白酶抑制剂有关的基因。T4 期上调与木质素纤维素合酶有关的基因，表明细胞壁的强化提高了对榆绿毛萤叶甲损伤的抗性。
结果表明，榆绿毛萤叶甲的取食导致榆基因的差异表达，并影响细胞能量代谢。榆对榆绿毛萤叶甲的这种生理反应和基因表达的变化构成了胆形成的生理和分子基础，可能提高了榆对榆绿毛萤叶甲的抗性。
