title: Genetic framework for flowering-time regulation by ambient temperature-responsive miRNAs in Arabidopsis.
abstract: Flowering is the primary trait affected by ambient temperature changes. Plant microRNAs (miRNAs) are small non-coding RNAs playing an important regulatory role in plant development. In this study, to elucidate the mechanism of flowering-time regulation by small RNAs, we identified six ambient temperature-responsive miRNAs (miR156, miR163, miR169, miR172, miR398 and miR399) in Arabidopsis via miRNA microarray and northern hybridization analyses. We also determined the expression profile of 120 unique miRNA loci in response to ambient temperature changes by miRNA northern hybridization analysis. The expression of the ambient temperature-responsive miRNAs and their target genes was largely anticorrelated at two different temperatures (16 and 23 degrees C). Interestingly, a lesion in short vegetative phase (SVP), a key regulator within the thermosensory pathway, caused alteration in the expression of miR172 and a subset of its target genes, providing a link between a thermosensory pathway gene and miR172. The miR172-overexpressing plants showed a temperature-independent early flowering phenotype, suggesting that modulation of miR172 expression leads to temperature insensitivity. Taken together, our results suggest a genetic framework for flowering-time regulation by ambient temperature-responsive miRNAs under non-stress temperature conditions.
authors.affiliation: Creative Research Initiatives, School of Life Sciences and Biotechnology, Korea University, Seoul 136-701, Korea.
authors.forename: Hanna
authors.initials: H
authors.lastname: Lee
authors.forename: Seong Jeon
authors.initials: SJ
authors.lastname: Yoo
authors.forename: Jeong Hwan
authors.initials: JH
authors.lastname: Lee
authors.forename: Wanhui
authors.initials: W
authors.lastname: Kim
authors.forename: Seung Kwan
authors.initials: SK
authors.lastname: Yoo
authors.forename: Heather
authors.initials: H
authors.lastname: Fitzgerald
authors.forename: James C
authors.initials: JC
authors.lastname: Carrington
authors.forename: Ji Hoon
authors.initials: JH
authors.lastname: Ahn
mesh_terms: D017360:Arabidopsis / Q000235:genetics* / Q000254:growth & development / Q000378:metabolism; D035264:Flowers / Q000235:genetics* / Q000254:growth & development / Q000378:metabolism; D020869:Gene Expression Profiling; D018506:Gene Expression Regulation, Plant; D035683:MicroRNAs / Q000235:genetics / Q000378:metabolism*; D009154:Mutation; D013696:Temperature
chemical_list: D035683:MicroRNAs