title: Dynamic changes of small RNAs in rice spikelet development reveal specialized reproductive phasiRNA pathways.
abstract: Dissection of the genetic pathways and mechanisms by which anther development occurs in grasses is crucial for both a basic understanding of plant development and for examining traits of agronomic importance such as male sterility. In rice, MULTIPLE SPOROCYTES1 (MSP1), a leucine-rich-repeat receptor kinase, plays an important role in anther development by limiting the number of sporocytes. OsTDL1a (a TPD1-like gene in rice) encodes a small protein that acts as a cofactor of MSP1 in the same regulatory pathway. In this study, we analyzed small RNA and mRNA changes in different stages of spikelets from wild-type rice, and from msp1 and ostdl1a mutants. Analysis of the small RNA data identified miRNAs demonstrating differential abundances. miR2275 was depleted in the two rice mutants; this miRNA is specifically enriched in anthers and functions to trigger the production of 24-nt phased secondary siRNAs (phasiRNAs) from PHAS loci. We observed that the 24-nt phasiRNAs as well as their precursor PHAS mRNAs were also depleted in the two mutants. An analysis of co-expression identified three Argonaute-encoding genes (OsAGO1d, OsAGO2b, and OsAGO18) that accumulate transcripts coordinately with phasiRNAs, suggesting a functional relationship. By mRNA in situ analysis, we demonstrated a strong correlation between the spatiotemporal pattern of these OsAGO transcripts and phasiRNA accumulations.
authors.affiliation: Department of Plant & Soil Sciences and Delaware Biotechnology Institute, University of Delaware, Newark, DE 19711, USA.
authors.forename: Qili
authors.initials: Q
authors.lastname: Fei
authors.affiliation: State Key Laboratory of Hybrid Rice, Joint International Research Laboratory of Metabolic and Developmental Sciences, Shanghai Jiao Tong University and University of Adelaide Joint Centre for Agriculture and Health, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai 200240, China.
authors.forename: Li
authors.initials: L
authors.lastname: Yang
authors.affiliation: State Key Laboratory of Hybrid Rice, Joint International Research Laboratory of Metabolic and Developmental Sciences, Shanghai Jiao Tong University and University of Adelaide Joint Centre for Agriculture and Health, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai 200240, China.
authors.forename: Wanqi
authors.initials: W
authors.lastname: Liang
authors.affiliation: State Key Laboratory of Hybrid Rice, Joint International Research Laboratory of Metabolic and Developmental Sciences, Shanghai Jiao Tong University and University of Adelaide Joint Centre for Agriculture and Health, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai 200240, China bmeyers@danforthcenter.org zhangdb@sjtu.edu.cn.|School of Agriculture, Food and Wine, University of Adelaide, South Australia 5064, Australia.
authors.forename: Dabing
authors.initials: D
authors.lastname: Zhang
authors.affiliation: Department of Plant & Soil Sciences and Delaware Biotechnology Institute, University of Delaware, Newark, DE 19711, USA bmeyers@danforthcenter.org zhangdb@sjtu.edu.cn.|Donald Danforth Plant Science Center, 975 North Warson Road, St. Louis, MO 63132, USA.|University of Missouri - Columbia, Division of Plant Sciences, 52 Agriculture Lab, Columbia, MO 65211, USA.
authors.forename: Blake C
authors.identifier: 0000-0003-3436-6097
authors.initials: BC
authors.lastname: Meyers
mesh_terms: D060565:Argonaute Proteins / Q000235:genetics / Q000502:physiology; D018506:Gene Expression Regulation, Plant / Q000235:genetics / Q000502:physiology; D017343:Genes, Plant; D017403:In Situ Hybridization; D035683:MicroRNAs / Q000235:genetics* / Q000502:physiology; D009154:Mutation; D012275:Oryza / Q000235:genetics* / Q000378:metabolism / Q000502:physiology; D018749:RNA, Plant / Q000235:genetics* / Q000378:metabolism / Q000502:physiology; D034741:RNA, Small Interfering / Q000235:genetics / Q000502:physiology; D012098:Reproduction / Q000235:genetics / Q000502:physiology
chemical_list: D060565:Argonaute Proteins; D035683:MicroRNAs; D018749:RNA, Plant; D034741:RNA, Small Interfering
keywords: Anther; Argonaute; microRNA; phasiRNA; rice; spikelet.