Knockdown NRPC2, 3, 8, NRPABC1 and NRPABC2 Affects RNAPIII Activity and Disrupts Seed Development in Arabidopsis

• Published in: International journal of molecular sciences 2021-10, Vol.22 (21), p.11314
• Main Authors: Zhao, Hailiang, Qin, Yao, Xiao, Ziyi, Liang, Kun, Gong, Dianming, Sun, Qin, Qiu, Fazhan
• Format: Article
• Language: English
• Subjects: 5S rRNA; Abscisic acid; Arabidopsis; Arabidopsis - genetics; Arabidopsis - metabolism; Arabidopsis Proteins - genetics; Carbohydrates; Cell death; Cell division; Cell growth; Cell proliferation; Cytokinins; Cytokinins - metabolism; DNA-directed RNA polymerase; Embryos; Gene expression; Gene Expression - genetics; Gene Expression Profiling - methods; Gene Expression Regulation, Plant - genetics; Genes; Jasmonic acid; Kinases; Lipids; Mutants; Mutation; Network analysis; Phenotypes; Proteins; RNA Polymerase III - genetics; RNA Polymerase III - metabolism; RNA polymerase III subunits; RNA, Transfer - genetics; rRNA 5S; seed development; Seeds; Seeds - genetics; Seeds - growth & development; Signal transduction; Transcription; Transcription, Genetic; Transcriptome - genetics; tRNA
• ISSN: 1422-0067; 1661-6596; 1422-0067
• DOI: 10.3390/ijms222111314

RNA polymerase III (RNAPIII) contains 17 subunits forming 4 functional domains that control the different stages of RNAPIII transcription and are dedicated to the synthesis of small RNAs such as 5S rRNA and tRNAs. Here, we identified 23 genes encoding these subunits in Arabidopsis ( ) and further analyzed 5 subunits (NRPC2, NRPC3, NRPC8, NRPABC1, and NRPABC2) encoded by 6 genes with different expression patterns and belonging to different sub-complexes. The knockdown of these genes repressed the expression of 5S rRNA and tRNAs, causing seed developmental arrest at different stages. Among these knockdown mutants, RNA-seq analysis revealed 821 common differentially expressed genes (DEGs), significantly enriched in response to stress, abscisic acid, cytokinins, and the jasmonic acid signaling pathway. Weighted gene co-expression network analysis (WGCNA) revealed several hub genes involved in embryo development, carbohydrate metabolic and lipid metabolic processes. We identified numerous unique DEGs between the mutants belonging to pathways, including cell proliferation, ribosome biogenesis, cell death, and tRNA metabolic processes. Thus, , , , , and control seed development in Arabidopsis by influencing RNAPIII activity and, thus, hormone signaling. Reduced expression of these subunit genes causes an insufficient accumulation of the total RNAPIII, leading to the phenotypes observed following the genetic knockdown of these subunits.