The cold-induced transcription factor bHLH112 promotes artemisinin biosynthesis indirectly via ERF1 in Artemisia annua
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Basic helix-loop-helix (bHLH) proteins are the second largest family of transcription factors (TFs) involved in developmental and physiological processes in plants. In this study, 205 putative bHLH TF genes were identified in the genome of Artemisia annua and expression of 122 of these was determined from transcriptomes used to construct the genetic map of A. annua. Analysis of gene expression association allowed division of the 122 bHLH TFs into five groups. Group V, containing 15 members, was tightly associated with artemisinin biosynthesis genes. Phylogenetic analysis indicated that two bHLH TFs, AabHLH106 and AabHLH112, were clustered with Arabidopsis ICE proteins. AabHLH112 was induced by low temperature, while AabHLH106 was not. We therefore chose AabHLH112 for further examination. AabHLH112 was highly expressed in glandular secretory trichomes, flower buds, and leaves. Dual-luciferase assays demonstrated that AabHLH112 enhanced the promoter activity of artemisinin biosynthesis genes and AaERF1, an AP2/ERF TF that directly and positively regulates artemisinin biosynthesis genes. Yeast one-hybrid assays indicated that AabHLH112 could bind to the AaERF1 promoter, but not to the promoters of artemisinin biosynthesis genes. Overexpression of AabHLH112 significantly up-regulated the expression levels of AaERF1 and artemisinin biosynthesis genes and consequently promoted artemisinin production.
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Various environmental stresses like heavy metal pollution, cold, water (drought and flooding), light, pest and disease damage affect accumulation of specialty metabolites in plants including artemisinin in A. annua.
“Besides elicitors and plant growth regulators, various environmental stresses like heavy metal pollution, cold, water (drought and flooding), light, pest and disease damage affect accumulation of specialty metabolites in plants including artemisinin in A. annua (Xiang et al. 2019; Hao et al. 2019; Soni and Abdin 2017; Yin et al. 2008).”
From Enhancing artemisinin content in and delivery from Artemisia annua: a review of alternative, classical, and transgenic approaches (2021) · cites this paper as Xiang et al. 2019
The Introduction (page not provided) says that temperature, water, and light affect secondary-metabolite biosynthesis, including artemisinin, and specifically describes increased artemisinin production under cold conditions. It does not address heavy-metal pollution, flooding, or pest and disease damage; the cited reference to water deficit supports drought only indirectly. (LLM, conf=0.86)
Experimental — accuracy not yet measuredExpression of these genes occurs in a coordinated manner under low temperature, hinting at participation of specific transcription factors in regulating artemisinin biosynthesis under such conditions.
“Expression of these genes occurs in a coordinated manner under low temperature, hinting at the participation of certain specific transcription factors in regulating artemisinin biosynthesis under such conditions (Xiang et al. 2019).”
From Enhancing artemisinin content in and delivery from Artemisia annua: a review of alternative, classical, and transgenic approaches (2021) · cites this paper as Xiang et al. 2019
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Wani, K. I., Choudhary, S., Zehra, A., Naeem, M., Weathers, P., & Aftab, T. (2021) · Planta · doi:10.1007/s00425-021-03676-3 · Cited by 74 · see citing works
- Authors
- Xiang, L., Jian, D., Zhang, F., Yang, C., Bai, G., Lan, X., Chen, M., Tang, K., & Liao, Z.
- Affiliations
- Southwest University (CN)
- Tobacco Breeding and Biotechnology Research Center, Yunnan Academy of Tobacco Agricultural Sciences, Key Laboratory of Tobacco Biotechnological Breeding, National Tobacco Genetic Engineering Research Center, Kunming, China
- TAAHC-SWU Medicinal Plant Joint R&D Centre, Xizang Agricultural and Husbandry College, Nyingchi of Tibet, China
- Shanghai Jiao Tong University (CN)
- Corresponding author
- Liao, Zhihua
- Venue
- Journal of Experimental Botany
- Publisher
- Oxford University Press (OUP)
- Published
- 2019-05-14
- Volume
- 70
- Issue
- 18
- Pages
- 4835-4848
- ISSN
- 0022-0957 (ISSN-L)
- 1460-2431
- PMC
- PMC6760284
- OpenAlex
- W2944837707
- Cited by
- 84
- References
- 72
- Citations by year
- 2026: 13 · 2025: 10 · 2024: 14 · 2023: 16 · 2022: 16 · 2021: 13 · 2020: 2
- FWCI
- 2.56
- Type
- journal article
- Language
- en
- Open access
- hybrid
- doi.org
- Licence
- Locations
- Journal of Experimental Botany (publishedVersion, cc-by-nc)
- PubMed Central (publishedVersion, cc-by-nc)
- PubMed (publishedVersion)
- Funders
- NSFC (31770335, 81803660)
- Foundation of YNTC (2016YN22)
- Shanghai Key Discipline Cultivation and Construction Project (ZXDF150005)
- Topics
- Life Sciences › Biochemistry, Genetics and Molecular Biology › Molecular Biology › Plant biochemistry and biosynthesis
- Life Sciences › Biochemistry, Genetics and Molecular Biology › Molecular Biology › Plant Gene Expression Analysis
- Life Sciences › Agricultural and Biological Sciences › Plant Science › Plant Molecular Biology Research
- Keywords
- bHLH transcription factors, artemisinin biosynthesis, eRF1, Artemisia annua, cold stress, transcriptional regulation, AP2/ERF transcription factors, transcriptional activation, low temperature induction
- MeSH terms
- Cold Temperature, Peptide Termination Factors, Phylogeny, Plant Proteins, Plant Leaves, Gene Expression Profiling, Artemisia annua, Flowers, Artemisinins, Basic Helix-Loop-Helix Transcription Factors, Basic Helix-Loop-Helix Proteins, Trichomes
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