Exogenous GA3 Application Enhances Xylem Development and Induces the Expression of Secondary Wall Biosynthesis Related Genes in Betula platyphylla

International Journal of Molecular Sciences

Huiyan Guo¹  Yucheng Wang¹  Huizi Liu¹  Ping Hu¹  Yuanyuan Jia¹  Chunrui Zhang¹  Yanmin Wang¹  Shan Gu²  Chuanping Yang¹  Chao Wang¹ 

[1] State Key Laboratory of Tree Genetics and Breeding, Northeast Forestry University, 26 Hexing Road, Harbin 150040, China; E-Mails:;Department of Life Science and Technology, Mudanjiang Normal College, Mudanjiang 157012, China; E-Mail:

关键词: Betula platyphylla SUK;    GA₃;    seed germination;    xylem development;    secondary wall biosynthesis related genes;   

DOI  :  10.3390/ijms160922960

来源: mdpi

【 摘 要 】

Gibberellin (GA) is a key signal molecule inducing differentiation of tracheary elements, fibers, and xylogenesis. However the molecular mechanisms underlying the effect of GA on xylem elongation and secondary wall development in tree species remain to be determined. In this study, Betula platyphylla (birch) seeds were treated with 300 ppm GA₃ and/or 300 ppm paclobutrazol (PAC), seed germination was recorded, and transverse sections of hypocotyls were stained with toluidine blue; the two-month-old seedlings were treated with 50 μM GA₃ and/or 50 μM PAC, transverse sections of seedling stems were stained using phloroglucinol–HCl, and secondary wall biosynthesis related genes expression was analyzed by real-time quantitative PCR. Results indicated that germination percentage, energy and time of seeds, hypocotyl height and seedling fresh weight were enhanced by GA₃, and reduced by PAC; the xylem development was wider in GA₃-treated plants than in the control; the expression of NAC and MYB transcription factors, CESA, PAL, and GA oxidase was up-regulated during GA₃ treatment, suggesting their role in GA₃-induced xylem development in the birch. Our results suggest that GA₃ induces the expression of secondary wall biosynthesis related genes to trigger xylogenesis in the birch plants.

【 授权许可】

CC BY   
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