Epigenetic and transcriptional responses underlying mangrove adaptation to UV-B

Yushuai Wang; Chenglong Huang; Weishun Zeng; Tianyuan Zhang; Cairong Zhong; Shulin Deng; Tian Tang

doi:10.1016/j.isci.2021.103148

Epigenetic and transcriptional responses underlying mangrove adaptation to UV-B

iScience. 2021 Sep 20;24(10):103148. doi: 10.1016/j.isci.2021.103148. eCollection 2021 Oct 22.

Authors

Yushuai Wang¹, Chenglong Huang¹, Weishun Zeng¹, Tianyuan Zhang¹, Cairong Zhong², Shulin Deng^{3

4}, Tian Tang¹

Affiliations

¹ State Key Laboratory of Biocontrol and Guangdong Key Laboratory of Plant Resources, School of Life Sciences, Sun Yat-sen University, Guangzhou 510275, Guangdong, People's Republic of China.
² Hainan Academy of Forestry (Hainan Academy of Mangrove), Haikou 571100, Hainan, People's Republic of China.
³ CAS Key Laboratory of South China Agricultural Plant Molecular Analysis and Genetic Improvement & Guangdong Provincial Key Laboratory of Applied Botany, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou 510650, People's Republic of China.
⁴ Xiaoliang Research Station for Tropical Coastal Ecosystems, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou 510650, People's Republic of China.

Abstract

Tropical plants have adapted to strong solar ultraviolet (UV) radiation. Here we compare molecular responses of two tropical mangroves Avecennia marina and Rhizophora apiculata to high-dose UV-B. Whole-genome bisulfate sequencing indicates that high UV-B induced comparable hyper- or hypo-methylation in three sequence contexts (CG, CHG, and CHH, where H refers to A, T, or C) in A. marina but mainly CHG hypomethylation in R. apiculata. RNA and small RNA sequencing reveals UV-B induced relaxation of transposable element (TE) silencing together with up-regulation of TE-adjacent genes in R. apiculata but not in A. marina. Despite conserved upregulation of flavonoid biosynthesis and downregulation of photosynthesis genes caused by high UV-B, A. marina specifically upregulated ABC transporter and ubiquinone biosynthesis genes that are known to be protective against UV-B-induced damage. Our results point to divergent responses underlying plant UV-B adaptation at both the epigenetic and transcriptional level.

Keywords: molecular biology; plant biology; transcriptomics.