title: MicroRNAs in the shoot apical meristem of soybean.
abstract: Plant microRNAs (miRNAs) play crucial regulatory roles in various developmental processes. In this study, we characterize the miRNA profile of the shoot apical meristem (SAM) of an important legume crop, soybean, by integrating high-throughput sequencing data with miRNA microarray analysis. A total of 8423 non-redundant sRNAs were obtained from two libraries derived from micro-dissected SAM or mature leaf tissue. Sequence analysis allowed the identification of 32 conserved miRNA families as well as 8 putative novel miRNAs. Subsequent miRNA profiling with microarrays verified the expression of the majority of these conserved and novel miRNAs. It is noteworthy that several miRNAs* were expressed at a level similar to or higher than their corresponding mature miRNAs in SAM or mature leaf, suggesting a possible biological function for the star species. In situ hybridization analysis revealed a distinct spatial localization pattern for a conserved miRNA, miR166, and its star speciessuggesting that they serve different roles in regulating leaf development. Furthermore, localization studies showed that a novel soybean miRNA, miR4422a, was nuclear-localized. This study also indicated a novel expression pattern of miR390 in soybean. Our approach identified potential key regulators and provided vital spatial information towards understanding the regulatory circuits in the SAM of soybean during shoot development.
authors.affiliation: ARC Centre of Excellence for Integrative Legume Research, Faculty of Land and Food Resources, The University of Melbourne, Parkville, Victoria, 3010, Australia.
authors.forename: Chui E
authors.initials: CE
authors.lastname: Wong
authors.forename: Ying-Tao
authors.initials: YT
authors.lastname: Zhao
authors.forename: Xiu-Jie
authors.initials: XJ
authors.lastname: Wang
authors.forename: Larry
authors.initials: L
authors.lastname: Croft
authors.forename: Zhong-Hua
authors.initials: ZH
authors.lastname: Wang
authors.forename: Farzad
authors.initials: F
authors.lastname: Haerizadeh
authors.forename: John S
authors.initials: JS
authors.lastname: Mattick
authors.forename: Mohan B
authors.initials: MB
authors.lastname: Singh
authors.forename: Bernard J
authors.initials: BJ
authors.lastname: Carroll
authors.forename: Prem L
authors.initials: PL
authors.lastname: Bhalla
mesh_terms: D001483:Base Sequence; D017124:Conserved Sequence / Q000235:genetics; D018506:Gene Expression Regulation, Plant; D017403:In Situ Hybridization; D018519:Meristem / Q000235:genetics* / Q000648:ultrastructure; D035683:MicroRNAs / Q000235:genetics* / Q000378:metabolism; D008969:Molecular Sequence Data; D018515:Plant Leaves / Q000235:genetics; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D018749:RNA, Plant / Q000235:genetics / Q000378:metabolism; D017422:Sequence Analysis, DNA; D013025:Glycine max / Q000235:genetics* / Q000648:ultrastructure
chemical_list: D035683:MicroRNAs; D012333:RNA, Messenger; D018749:RNA, Plant