,A Plant SMALL RNA-BINDING PROTEIN 1 Family Mediates Cell-to-Cell Trafficking of RNAi Signals

• 作 者: Yan Yan Byung-Kook Ham Yee Hang Chong Shyi-Dong Yeh William J.Lucas
• 机 构: Department of Plant Biology, College of Biological Sciences, University of California, Davis, CA 956
• 出 处: 分子植物（英文版）
• 发表日期: 2020年2期
• 关键词: RNAi small RNA-binding protein family small RNA movement non-cell-autonomous pro

In plants,RNA interference (RNAi) plays a pivotal role in growth and development,and responses to environmental inputs,including pathogen attack.The intercellular and systemic trafficking of small interfering RNA (siRNA)/microRNA (miRNA) is a central component in this regulatory pathway.Currently,little is known with regards to the molecular agents involved in the movement of these si/miRNAs.To address this situation,we employed a biochemical approach to identify and characterize a conserved SMALL RNA-BINDING PROTEIN 1 (SRBP1) family that mediates non-cell-autonomous small RNA (sRNA) trafficking.In Arabidopsis,AtSRBP1 is a glycine-rich (GR) RNA-binding protein,also known as AtGRP7,which we show binds single-stranded siRNA.A viral vector,Zucchini yellow mosaic virus (ZYMV),was employed to functionally characterized the AtSRBP1-4 (AtGRP7/2/4/8) RNA recognition motif and GR domains.Cellular-based studies revealed the GR domain as being necessary and sufficient for SRBP1 cell-to-cell movement.Taken together,our findings provide a foundation for future research into the mechanism and function of mobile sRNA signaling agents in plants.