|BOUTANAEV, ALEXANDER - Russian Academy Of Sciences|
|POSTNIKOVA, OLGA - Oak Ridge Institute For Science And Education (ORISE)|
Submitted to: Scientific Reports
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 5/24/2016
Publication Date: 6/10/2016
Citation: Nemchinov, L.G., Boutanaev, A.M., Postnikova, O.A. 2016. Virus-induced gene silencing of RPC5-like subunit of RNA polymerase III caused pleiotropic effects in Nicotiana benthamiana. Scientific Reports. 6:27785.
Interpretive Summary: Transcription is a fundamental mechanism in all living cells. In plants, all genes are transcribed by five nuclear RNA polymerases that have distinct functional roles. RNA polymerase III transcribes housekeeping genes that are essential for cell maintenance. It is assembled from 17 different subunits and vast majority of available information on the enzyme has derived from human and yeast sources. The RPC5 is one of the 17 subunits and its exact functional role in the transcription is poorly understood. In this work, using modern tools of functional genomics, we demonstrated that activity of RPC5 subunit is overall critical for proper functionality of RNA polymerase III and for the normal plant development. The findings offer insight into what might happen if transcription of the RPC5 in plants is inhibited. The acquired knowledge will improve our understanding of the basic molecular processes in eukaryotic cells.
Technical Abstract: In eukaryotic cells, RNA polymerase III is highly conserved, contains 17 subunits and transcribes housekeeping genes such as ribosomal 50S rRNA, tRNA and other small RNAs. Functional roles of the RPC5 are poorly characterized in the literature. In this work, we report that virus-induced gene silencing of transcripts encoding a putative RPC5-like subunit of the RNA Polymerase III in a model species Nicotiana benthamiana caused a pleiotropic effect, including but not limited to severe dwarfing appearance, chlorosis, nearly complete reduction of internodes and abnormal leaf shape. Using transcriptomic analysis, we identified genes and pathways affected by RPC5 silencing and thus presumably related to the cellular roles of the subunit as well as to the downstream cascade of reaction in response to partial loss of RNA Polymerase III function. Our results suggest that silencing of the RPC5L in N. benthamiana disrupted not only functions commonly associated with the core RNAPIII transcripts, but also more diverse cellular processes, including responses to stress. We believe this is the first demonstration that activity of RPC5 subunit is overall critical for proper RNAPIII functionality and the normal plant development.