caa a22 4500 606208208 CHVBK 20210128101021.0 cr unu---uuuuu 210128e20151001xx s 000 0 eng 10.1007/s00425-015-2323-3 doi (NATIONALLICENCE)springer-10.1007/s00425-015-2323-3 Deciphering UV-B-induced variation in DNA methylation pattern and its influence on regulation of DBR2 expression in Artemisia annua L [Elektronische Daten] [Neha Pandey, Shashi Pandey-Rai] Main conclusion : UV-B-caused DNA hypomethylation and UV-B-mediated epigenetic activation of additional WRKY-binding site(s) in the DBR2 promoter may contribute to the overexpression of the DBR2 gene in Artemisia annua. DNA methylation is one of the key mechanisms behind stress-induced transcriptional switch off/on. Here, we evaluate the DNA methylation level in response to UV-B radiation in Artemisia annua which produces artemisinin, a sesquiterpene that has been recommended by WHO for the frontline treatment of malaria. However, the drug is facing serious shortage due to its low concentration in plants. UV-B treatment (3h) enhanced artemisinin concentration up to 1.91-fold as compared to control. A key regulatory gene of artemisinin biosynthesis, DBR2 was upregulated under UV-B. This study presents observations regarding contributions of DNA methylation to the gene regulation using DBR2 as an example. Restriction digestion of genomic DNA by isoschizomers (MspI and HpaII) suggested UV-B involvement in DNA hypomethylation in A. annua. The global level of DNA methylation (R) was 3.4 and 5.9% for UV-B treated and control plants, respectively, attesting hypomethylation of DNA in response to UV-B. Further bisulfite sequencing PCR showed demethylation at two CHG sites in 18S rRNA gene. Similarly, bisulfite sequencing of promoter region of DBR2 has demonstrated demethylation at 4 CG-, 4 CHH- and 2 CHG-sites. In silico analysis revealed UV-B-mediated demethylation at seven putative transcription factor binding sites including WRKY, which are positive regulators of artemisinin biosynthesis. UV-B treatment has resulted in activation of additional WRKY-binding site in UV-B-treated plants compared with single active WRKY-binding site in control and this could be the probable reason for overexpression of DBR2. It is suggested that DNA demethylation is an important epigenetic response to UV-B radiation in A. annua that surely will provide new horizons to further elucidate the mechanistic evidence of plant's responses to UV-B radiation. Springer-Verlag Berlin Heidelberg, 2015 DNA methylation nationallicence Bisulfite sequencing PCR nationallicence Artemisia annua nationallicence DBR2 promoter nationallicence WRKY nationallicence Pandey Neha Laboratory of Morphogenesis, Department of Botany, Faculty of Science, Banaras Hindu University, 221005, Varanasi, Uttar Pradesh, India aut Pandey-Rai Shashi Laboratory of Morphogenesis, Department of Botany, Faculty of Science, Banaras Hindu University, 221005, Varanasi, Uttar Pradesh, India aut Planta Springer Berlin Heidelberg 242/4(2015-10-01), 869-879 0032-0935 242:4<869 2015 242 425 https://doi.org/10.1007/s00425-015-2323-3 text/html Onlinezugriff via DOI BK010053 XK010053 XK010000 Metadata rights reserved Springer special CC-BY-NC licence nationallicence 1 research-article jats NATIONALLICENCE NATIONALLICENCE NL-springer NATIONALLICENCE 856 40 https://doi.org/10.1007/s00425-015-2323-3 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Pandey Neha Laboratory of Morphogenesis, Department of Botany, Faculty of Science, Banaras Hindu University, 221005, Varanasi, Uttar Pradesh, India aut NATIONALLICENCE 700 1- Pandey-Rai Shashi Laboratory of Morphogenesis, Department of Botany, Faculty of Science, Banaras Hindu University, 221005, Varanasi, Uttar Pradesh, India aut NATIONALLICENCE 773 0- Planta Springer Berlin Heidelberg 242/4(2015-10-01), 869-879 0032-0935 242:4<869 2015 242 425