title: TamiR1123 originated from a family of miniature inverted-repeat transposable elements (MITE) including one inserted in the Vrn-A1a promoter in wheat.
abstract: More than half of spring wheat cultivars have a dominant Vrn-A1a allele that has an insertion of a miniature inverted-repeat transposable element (MITE) in its promoter. In this study, we found that the MITE present in the Vrn-A1a gene (MITE_VRN) is a nearly perfect palindrome and it can form highly stable hairpin loops when expressed as RNA. MITE_VRN also possessed sequences of a microRNA in Triticum aestivum (TamiR1123). The P(32) labeled TamiR1123 probe detected two RNA molecules on a small RNA gel blot, one expected for MITE_VRN, and the other expected for TamiR1123. These results demonstrated that MITE_VRN was expressed as RNAs and TamiR1123 was originated from the MITE_VRN family. The isogenic line TDD carrying the dominant Vrn-A1a allele with MITE_VRN showed higher TamiR1123 and Vrn-A1a transcript levels than the isogenic line TDE carrying the recessive vrn-A1a allele without MITE_VRN. TamiR1123 were greatly up-regulated by plant age but slightly down-regulated by low temperature and short days. These findings have pointed to alternative regulatory mechanisms for plant development governed by Vrn-A1a in spring wheat.
authors.affiliation: Department of Plant and Soil Sciences, Oklahoma State University, Stillwater, OK 74078, USA.
authors.forename: Ming
authors.initials: M
authors.lastname: Yu
authors.affiliation: Department of Plant and Soil Sciences, Oklahoma State University, Stillwater, OK 74078, USA.
authors.forename: Brett F
authors.initials: BF
authors.lastname: Carver
authors.affiliation: Department of Plant and Soil Sciences, Oklahoma State University, Stillwater, OK 74078, USA. Electronic address: liuling.yan@okstate.edu.
authors.forename: Liuling
authors.initials: L
authors.lastname: Yan
mesh_terms: D000483:Alleles; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism; D004251:DNA Transposable Elements; D018506:Gene Expression Regulation, Plant; D017343:Genes, Plant; D055029:Inverted Repeat Sequences; D035683:MicroRNAs; D017440:Photoperiod; D063245:Plant Development / Q000235:genetics*; D011401:Promoter Regions, Genetic; D018749:RNA, Plant; D012097:Repressor Proteins / Q000235:genetics / Q000378:metabolism; D012621:Seasons; D013696:Temperature; D014908:Triticum / Q000235:genetics*
chemical_list: D029681:Arabidopsis Proteins; D004251:DNA Transposable Elements; D035683:MicroRNAs; D018749:RNA, Plant; D012097:Repressor Proteins; C461388:VRN1 protein, Arabidopsis
keywords: Flowering time; MITE; VRN1; Vernalization; Wheat; microRNA