title: Biogenesis of phased siRNAs on membrane-bound polysomes in Arabidopsis.
abstract: Small RNAs are central players in RNA silencing, yet their cytoplasmic compartmentalization and the effects it may have on their activities have not been studied at the genomic scale. Here we report that Arabidopsis microRNAs (miRNAs) and small interfering RNAs (siRNAs) are distinctly partitioned between the endoplasmic reticulum (ER) and cytosol. All miRNAs are associated with membrane-bound polysomes (MBPs) as opposed to polysomes in general. The MBP association is functionally linked to a deeply conserved and tightly regulated activity of miRNAs - production of phased siRNAs (phasiRNAs) from select target RNAs. The phasiRNA precursor RNAs, thought to be noncoding, are on MBPs and are occupied by ribosomes in a manner that supports miRNA-triggered phasiRNA production, suggesting that ribosomes on the rough ER impact siRNA biogenesis. This study reveals global patterns of cytoplasmic partitioning of small RNAs and expands the known functions of ribosomes and ER.
authors.affiliation: Agricultural Genomics Institute, Chinese Academy of Agricultural Sciences, Shenzhen, China.|Department of Botany and Plant Sciences, Institute of Integrative Genome Biology, University of California, Riverside, Riverside, United States.
authors.forename: Shengben
authors.initials: S
authors.lastname: Li
authors.affiliation: Department of Botany and Plant Sciences, Institute of Integrative Genome Biology, University of California, Riverside, Riverside, United States.
authors.forename: Brandon
authors.initials: B
authors.lastname: Le
authors.affiliation: Guangdong Provincial Key Laboratory for Plant Epigenetics, College of Life Sciences and Oceanography, Shenzhen University, Shenzhen, China.|State Key Laboratory of Plant Genomics and National Center for Plant Gene Research, Institute of Genetics and Developmental Biology, Beijing, China.
authors.forename: Xuan
authors.initials: X
authors.lastname: Ma
authors.affiliation: Department of Botany and Plant Sciences, Institute of Integrative Genome Biology, University of California, Riverside, Riverside, United States.
authors.forename: Shaofang
authors.initials: S
authors.lastname: Li
authors.affiliation: Department of Botany and Plant Sciences, Institute of Integrative Genome Biology, University of California, Riverside, Riverside, United States.|Guangdong Provincial Key Laboratory for Plant Epigenetics, College of Life Sciences and Oceanography, Shenzhen University, Shenzhen, China.
authors.forename: Chenjiang
authors.initials: C
authors.lastname: You
authors.affiliation: Department of Botany and Plant Sciences, Institute of Integrative Genome Biology, University of California, Riverside, Riverside, United States.
authors.forename: Yu
authors.initials: Y
authors.lastname: Yu
authors.affiliation: Department of Botany and Plant Sciences, Institute of Integrative Genome Biology, University of California, Riverside, Riverside, United States.
authors.forename: Bailong
authors.initials: B
authors.lastname: Zhang
authors.affiliation: Department of Botany and Plant Sciences, Institute of Integrative Genome Biology, University of California, Riverside, Riverside, United States.|Guangdong Provincial Key Laboratory for Plant Epigenetics, College of Life Sciences and Oceanography, Shenzhen University, Shenzhen, China.
authors.forename: Lin
authors.initials: L
authors.lastname: Liu
authors.affiliation: Department of Botany and Plant Sciences, Institute of Integrative Genome Biology, University of California, Riverside, Riverside, United States.|Guangdong Provincial Key Laboratory for Plant Epigenetics, College of Life Sciences and Oceanography, Shenzhen University, Shenzhen, China.
authors.forename: Lei
authors.initials: L
authors.lastname: Gao
authors.affiliation: Department of Botany and Plant Sciences, Institute of Integrative Genome Biology, University of California, Riverside, Riverside, United States.|College of Horticulture, Nanjing Agricultural University, Nanjing, China.
authors.forename: Ting
authors.initials: T
authors.lastname: Shi
authors.affiliation: Department of Botany and Plant Sciences, Institute of Integrative Genome Biology, University of California, Riverside, Riverside, United States.
authors.forename: Yonghui
authors.initials: Y
authors.lastname: Zhao
authors.affiliation: Guangdong Provincial Key Laboratory for Plant Epigenetics, College of Life Sciences and Oceanography, Shenzhen University, Shenzhen, China.
authors.forename: Beixin
authors.initials: B
authors.lastname: Mo
authors.affiliation: State Key Laboratory of Plant Genomics and National Center for Plant Gene Research, Institute of Genetics and Developmental Biology, Beijing, China.
authors.forename: Xiaofeng
authors.initials: X
authors.lastname: Cao
authors.affiliation: Department of Botany and Plant Sciences, Institute of Integrative Genome Biology, University of California, Riverside, Riverside, United States.|Guangdong Provincial Key Laboratory for Plant Epigenetics, College of Life Sciences and Oceanography, Shenzhen University, Shenzhen, China.|Howard Hughes Medical Institute, University of California, Riverside, Riverside, United States.
authors.forename: Xuemei
authors.identifier: 0000-0002-5209-1157
authors.initials: X
authors.lastname: Chen
mesh_terms: D017360:Arabidopsis / Q000166:cytology / Q000378:metabolism*; D004721:Endoplasmic Reticulum / Q000378:metabolism*; D007425:Intracellular Membranes / Q000378:metabolism*; D011132:Polyribosomes / Q000378:metabolism*; D034741:RNA, Small Interfering / Q000378:metabolism*
chemical_list: D034741:RNA, Small Interfering
keywords: a.thaliana; argonaute; chromosomes; endoplasmic reticulum; genes; microRNA; plant biology; polysome; rough ER; siRNA