《植物生理学报》 2015, 51(3): 363-369

酵母TPS1基因促进干旱胁迫下玉米的根系生长

项阳^1,*, 刘延波^1,2,*, 秦利军^1,2, 赵德刚^1,2,**

贵州大学¹生命科学学院/农业生物工程研究院, 山地植物资源保护与种质创新省部共建教育部重点实验室; ²绿色农药与农业生物工程国家重点实验室培育基地, 贵阳550025

通信作者：项阳；E-mail: dgzhao@gzu.edu.cn；Tel: 0851-83863615

摘　要：

本文对干旱胁迫下转酵母TPS1基因玉米的根系生长进行了研究。结果显示，经干旱胁迫后, 转基因玉米的根系较野生型相比, 根长和直径分别增加了79.3%和13.3%, 一级、二级侧根数、根系的总吸收面积、活跃吸收面积、比表面积和根系活力较野生型也极显著增加。对根系组织观察发现, 转TPS1基因玉米植株的根系细胞较大, 细胞纵向和横向显著增长。转基因玉米根系的生长素含量较野生型的高, 而其细胞分裂素含量则低。进一步对玉米根系生长相关基因的表达水平分析发现, 与生长素有关的根系生长正调控基因PLT1、PIN1、AUX/IAA、CRL1表达较野生型上调, 其中PLT1、AUX/IAA、CRL1的表达量比野生型的高2倍以上, 而与细胞分裂素有关的根系生长负调控基因WOX11、ARR2、ARR1表达较野生型下调, 比野生型的下降50%以上。

关键词：玉米; TPS1基因; 根系生长; 生长素; 细胞分裂素; 抗旱性

收稿：2014-10-22   修定：2015-01-21

资助：国家转基因生物新品种培育科技重大专项子课题任务(2014ZX0801008B-002)、国家转基因生物新品种培育科技重大专项子课题任务(2013ZX08010-003和2014ZX08010-003)和贵州省科技厅转基因专项(黔科合2004NZ004)。

Trehalose-6-Phosphate Synthase Gene TPS1 from Saccharomyces cerevisiae Improve Root Growth in Transgenic Maize Under Drought Stress

XIANG Yang^1,*, LIU Yan-Bo^1,2,*, QIN Li-Jun^1,2, ZHAO De-Gang^1,2,**

¹Key Laboratory of Plant Resources Conservation and Germplasm Innovation in Mountainous Region, Ministry of Education, Institute of Agro-Bioengineering and College of Life Sciences; ²The State Key Lab Breeding Base of Green Pesticide and Agricultural Biological Engineering, Guizhou University, Guiyang 550025, China

Corresponding author: XIANG Yang; E-mail: dgzhao@gzu.edu.cn; Tel: 0851-83863615

Abstract:

In this paper, we studied root growth in transgenic maize plants after drought stress. Compared with wild-type maize, root length and diameter of transgenic maize contained trehalose-6-phosphate synthase (TPS1) gene increased 79.3% and 13.3%, respectively. The number of first- and second-order lateral roots, the total of root absorption area, active absorption area, specific surface area, root activity in genetically modified maize significantly increased than wild-type. We found that root cells elongated vertically and horizontally in root tissue slices as well. The determination of auxin and cytokinin content indicated auxin content increased compared with wild type, but that of cytokinin decreased. Further, gene expression analysis showed that genes associated with auxin (PLT1, AUX/IAA, PIN1 and CRL1) up-regulated and expression level of PLT1, AUX/IAA and CRL1 was about 2 folds of wild type, while expression level of genes associated with cytokinin (WOX11, ARR2 and ARR1) dropped by more than 50% than wild-type.

Key words: maize; TPS1 gene; root growth; auxin; cytokinin; drought tolerance