文献类型： 外文期刊

作者： Hou, Xin ¹ ; Singh, Sanjay Kumar ² ; Werkman, Joshua R. ² ; Liu, Yongliang ² ; Yuan, Qinghua ³ ; Wu, Xia ² ; Patra, Barunava ² ; Sui, Xueyi ⁴ ; Lyu, Ruiqing ² ; Wang, Bingwu ⁴ ; Liu, Xiaoyu ⁵ ; Li, Yongqing ⁶ ; Ma, Wei ⁷ ; Pattanaik, Sitakanta ² ; Yuan, Ling ² ;

作者机构： 1.Shandong Agr Univ, Coll Plant Protect, Dept Tobacco, Shandong Prov Key Lab Agr Microbiol, Tai An 271018, Peoples R China

2.Univ Kentucky, Kentucky Tobacco Res & Dev Ctr, Dept Plant & Soil Sci, Lexington, KY 40546 USA

3.Guangdong Acad Agr Sci, Crops Res Inst,Guangdong Prov Engn & Technol, Key Lab Crop Genet Improvement Guangdong Prov, Res Ctr Tobacco Breeding & Comprehens Utilizat, Guangzhou 510640, Peoples R China

4.Yunnan Acad Tobacco Agr Sci, Tobacco Breeding & Biotechnol Res Ctr, Kunming 650021, Yunnan, Peoples R China

5.Shanxi Agr Univ, Pomol Inst, Taigu 030815, Shanxi, Peoples R China

6.Chinese Acad Sci, South China Bot Garden, Guangdong Prov Key Lab Appl Bot, Key Lab South China Agr Plant Mol Anal & Genet Imp, Guangzhou 510650, Peoples R China

7.Nanyang Technol Univ, Sch Biol Sci, Singapore 637551, Singapore

关键词： Transcriptional regulation; Protein-protein interaction; MYC2; MEDIATOR25; Homology structural modeling; Specialized metabolism

期刊名称：INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES （ 影响因子：8.2； 五年影响因子：7.8 ）

ISSN： 0141-8130

年卷期： 2023 年 252 卷

页码：

收录情况： SCI

摘要： The activity of bHLH transcription factor MYC2, a key regulator in jasmonate signaling and plant specialized metabolism, is sensitive to repression by JASMONATE-ZIM-domain (JAZ) proteins and co-activation by the mediator subunit MED25. The substitution of a conserved aspartic acid (D) to asparagine (N) in the JAZ-interacting domain (JID) of Arabidopsis MYC2 affects interaction with JAZ, although the mechanism remained unclear. The effects of the conserved residue MYC2(D128) on interaction with MED25 have not been investigated. Using tobacco as a model, we generated all possible substitutions of aspartic acid 128 (D128) in NtMYC2a. NtMYC2a(D128N) partially desensitized the repression by JAZ proteins, while strongly interacting with MED25, resulting in increased expression of nicotine pathway genes and nicotine accumulation in tobacco hairy roots overexpressing NtMYC2a(D128N) compared to those overexpressing NtMYC2a. The proline substitution, NtMYC2a(D128P), negatively affected transactivation and abolished the interaction with JAZ proteins and MED25. Structural modeling and simulation suggest that the overall stability of the JID binding pocket is a predominant cause for the observed effects of substitutions at D128. The D128N substitution has an overall stabilizing effect on the binding pocket, which is destabilized by D128P. Our study offers an innovative tool to increase the production of plant natural products.