《植物生理学报》 2016, 52(8): 1214-1222

玉米光合突变体bsd2 (bundle sheath defective II)的转录组分析

江芳^1,*, 丁泽红^2,*, 董雷³, 李平华^4,**

¹海南大学农学院, 海口570228; ²中国热带农业科学院热带生物技术研究所, 海口571101; ³河南农业大学农学院, 郑州450002; ⁴山东农业大学农学院, 山东泰安271018

通信作者：江芳；E-mail: pinghuali@sdau.edu.cn

摘　要：

玉米是典型的C₄植物, 具有独特的花环结构和二氧化碳浓缩机制, 因而具有较高的光合效率。BSD2 (bundle sheath defective II)基因主要在花环结构的维管束鞘细胞表达, 其缺失会造成维管束鞘细胞中的叶绿体发育异常, 从而影响叶片的光合作用。本研究对高光和低光下的野生型和bsd2突变体不同发育阶段的叶片进行RNA-seq测序。结果表明, BSD2基因缺失对叶片非光合部位影响较小; 对叶片光合部位影响较大。其中, 光合作用、淀粉和糖代谢、四吡咯生物合成等相关基因在bsd2突变体中显著下调, 而蛋白质合成与折叠、RNA加工与转录调节相关的基因显著上调。

关键词：玉米; C₄光合; 维管束鞘细胞缺失突变体II (bsd2); RNA-seq

收稿：2016-04-08   修定：2016-07-12

资助：国家自然科学基金(31271393)。

Transcriptome analysis on the maize photosynthetic mutant bsd2 (bundle sheath defective II)

JIANG Fang^1,*, DING Ze-Hong^2,*, DONG Lei³, LI Ping-Hua^4,**

¹College of Agronomic Sciences, Hainan University, Haikou 570228, China; ²Institute of Tropical Bioscience and Biotechnology, Chinese Academy of Tropical Agricultural Science, Haikou 571101, China; ³College of Agronomic Sciences, Henan Agricultural University, Zhengzhou 450002, China; ⁴College of Agronomic Sciences, Shandong Agricultural University, Taian, Shandong 271018, China

Corresponding author: JIANG Fang; E-mail: pinghuali@sdau.edu.cn

Abstract:

As a typical C₄ plant, maize (Zea mays) has specifically anatomical structure—‘Kranz structure’ and unique CO₂ concentration mechanism. Then it has high photosynthetic efficiency. Nucleus-encoded BSD2 gene expresses mainly in the bundle sheath cells of C₄-Kranz structure and its deficiency perturbs the chloroplast biosynthesis. In this study, we utilized RNA-Seq technology to monitor the transcriptome changes in different leaf sections between wild type and bsd2 mutant under different light intensity. The results indicated that the deficiency of BSD2 gene had little effect on the leaf sections that had not exposed to the light. However, for the leaf sections that exposed to the light, the transcriptome was dramatically influenced by the mutation of BSD2, with genes that involved in photosynthesis, starch and sugar metabolism and tetrapyrrole biosynthesis were significantly repressed and the genes related to the protein metabolism and RNA processing were significantly induced. Our research revealed the important function of BSD2 gene on the photosynthesis at the transcriptome level, which provides valuable information for understanding the mechanism of C₄ photosynthesis.

Key words: Zea mays; C₄ photosynthesis; bundle sheath cell; bundle sheath defective II mutant (bsd2); RNA sequencing (RNA-Seq)