Light controls mesophyll- specific posttranscriptional splicing of photoregulatory genes by AtPRMT5

• 成果类型: Article
• 署名作者: Yan, Yan; Luo, Haofei; Qin, Yuwei; Yan, Tingting; Jia, Jinbu; Hou, Yifeng; Liu, Zhijian; Zhai, Jixian; Long, Yanping; Deng, Xian; Cao, Xiaofeng
• 署名单位: Chinese Academy of Sciences; Institute of Genetics & Developmental Biology, CAS; Chinese Academy of Sciences; Institute of Genetics & Developmental Biology, CAS; Southern University of Science & Technology; Hainan Academy of Agricultural Sciences; Chinese Academy of Sciences; University of Chinese Academy of Sciences, CAS
• 刊物名称: PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA
• ISSN/ISSBN: 0027-8894
• DOI: 10.1073/pnas.2317408121
• 发表日期: 2024-02-06
• 关键词: circadian clock; intron retention; histone h4r3; arabidopsis; phytochrome; expression; protein; transcription; cop1; photomorphogenesis

摘要

Light plays a central role in plant growth and development, providing an energy source and governing various aspects of plant morphology. Previous study showed that many polyadenylated full- length RNA molecules within the nucleus contain unspliced introns (post- transcriptionally spliced introns, PTS introns), which may play a role in rapidly responding to changes in environmental signals. However, the mechanism underlying post- transcriptional regulation during initial light exposure of young, etiolated seedlings remains elusive. In this study, we used FLEP-seq2, a Nanopore-based sequencing technique, to analyze nuclear RNAs in Arabidopsis (Arabidopsis thaliana) seedlings under different light conditions and found numerous light- responsive PTS introns. We also used single- nucleus RNA sequencing (snRNA-seq) to profile transcripts in single nucleus and investigate the distribution of light- responsive PTS introns across distinct cell types. We established that light- induced PTS introns are predominant in mesophyll cells during seedling de- etiolation following exposure of etiolated seedlings to light. We further demonstrated the involvement of the splicing- related factor A. thaliana PROTEIN ARGININE METHYLTRANSFERASE 5 (AtPRMT5), working in concert with the E3 ubiquitin ligase CONSTITUTIVE PHOTOMORPHOGENIC 1 (COP1), a critical repressor of light signaling pathways. We showed that these two proteins orchestrate light- induced PTS events in mesophyll cells and facilitate chloroplast development, photosynthesis, and morphogenesis in response to ever- changing light conditions. These findings provide crucial insights into the intricate mechanisms underlying plant acclimation to light at the cell - type level.