Lingxiao He1, Huabing Liu2, Changhe Cheng2, Min Xu3, Lei He3, Lihua Li3, Jian Yao3, Wenjun Zhang4, Zhengguang Zhai4, Qinzhan Luo5, Jutao Sun1, Tiezhao Yang1, Shixiao Xu6. 1. College of Tobacco Science, Henan Agricultural University, National Tobacco Cultivation & Physiology & Biochemistry Research Centre, Scientific Observation and Experiment Station of Henan, Ministry of Agriculture, Zhengzhou, 450002, China. 2. Technology Center, China Tobacco Zhejiang Industry Co, Ltd., Hangzhou, 310008, China. 3. China National Tobacco Corporation Henan company, Zhengzhou, 450002, Henan, China. 4. Hunan Tobacco Corporation Changsha Company, Changsha, 410007, Hunan, China. 5. Guangxi Zhuang Autonomous Region Tobacco Corporation Baise Company, Baise, 533000, Guangxi, China. 6. College of Tobacco Science, Henan Agricultural University, National Tobacco Cultivation & Physiology & Biochemistry Research Centre, Scientific Observation and Experiment Station of Henan, Ministry of Agriculture, Zhengzhou, 450002, China. xushixiao@henau.edu.cn.
Abstract
BACKGROUND: Amber-like compounds form in tobacco (Nicotiana tabacum) during leaf curing and impact aromatic quality. In particular, cis-abienol, a polycyclic labdane-related diterpenoid, is of research interest as a precursor of these compounds. Glandular trichome cells specifically express copalyl diphosphate synthase (NtCPS2) at high levels in tobacco, which, together with NtABS, are major regulators of cis-abienol biosynthesis in tobacco. RESULTS: To identify the genes involved in the biosynthesis of cis-abienol in tobacco, we constructed transgenic tobacco lines based on an NtCPS2 gene-knockdown model using CRISPR/Cas9 genome-editing technology to inhibit NtCPS2 function in vitro. In mutant plants, cis-abienol and labdene diol contents decreased, whereas the gibberellin and abscisic acid (ABA) contents increased compared with those in wild-type tobacco plants. RNA sequencing analysis revealed the presence of 9514 differentially expressed genes (DEGs; 4279 upregulated, 5235 downregulated) when the leaves of wild-type and NtCPS2-knockdown tobacco plants were screened. Among these DEGs, the genes encoding cis-abienol synthase, ent-kaurene oxidase, auxin/ABA-related proteins, and transcription factors were found to be involved in various biological and physiochemical processes, including diterpenoid biosynthesis, plant hormone signal transduction, and plant-pathogen interactions. CONCLUSIONS: The present study provides insight into the unique transcriptome profile of NtCPS2 knockdown tobacco, allowing for a better understanding of the biosynthesis of cis-abienol in tobacco.
BACKGROUND: Amber-like compounds form in tobacco (Nicotiana tabacum) during leaf curing and impact aromatic quality. In particular, cis-abienol, a polycyclic labdane-related diterpenoid, is of research interest as a precursor of these compounds. Glandular trichome cells specifically express copalyl diphosphate synthase (NtCPS2) at high levels in tobacco, which, together with NtABS, are major regulators of cis-abienol biosynthesis in tobacco. RESULTS: To identify the genes involved in the biosynthesis of cis-abienol in tobacco, we constructed transgenic tobacco lines based on an NtCPS2 gene-knockdown model using CRISPR/Cas9 genome-editing technology to inhibit NtCPS2 function in vitro. In mutant plants, cis-abienol and labdene diol contents decreased, whereas the gibberellin and abscisic acid (ABA) contents increased compared with those in wild-type tobacco plants. RNA sequencing analysis revealed the presence of 9514 differentially expressed genes (DEGs; 4279 upregulated, 5235 downregulated) when the leaves of wild-type and NtCPS2-knockdown tobacco plants were screened. Among these DEGs, the genes encoding cis-abienol synthase, ent-kaurene oxidase, auxin/ABA-related proteins, and transcription factors were found to be involved in various biological and physiochemical processes, including diterpenoid biosynthesis, plant hormone signal transduction, and plant-pathogen interactions. CONCLUSIONS: The present study provides insight into the unique transcriptome profile of NtCPS2 knockdown tobacco, allowing for a better understanding of the biosynthesis of cis-abienol in tobacco.
Authors: Martin Jinek; Krzysztof Chylinski; Ines Fonfara; Michael Hauer; Jennifer A Doudna; Emmanuelle Charpentier Journal: Science Date: 2012-06-28 Impact factor: 47.728
Authors: Vijay Vontimitta; David A Danehower; Tyler Steede; Hyunsook S Moon; Ramsey S Lewis Journal: J Agric Food Chem Date: 2010-01-13 Impact factor: 5.279