title: Gene structures and processing of Arabidopsis thaliana HYL1-dependent pri-miRNAs.
abstract: Arabidopsis thaliana HYL1 is a nuclear double-stranded RNA-binding protein involved in the maturation of pri-miRNAs. A quantitative real-time PCR platform for parallel quantification of 176 pri-miRNAs was used to reveal strong accumulation of 57 miRNA precursors in the hyl1 mutant that completely lacks HYL1 protein. This approach enabled us for the first time to pinpoint particular members of MIRNA family genes that require HYL1 activity for efficient maturation of their precursors. Moreover, the accumulation of miRNA precursors in the hyl1 mutant gave us the opportunity to carry out 3' and 5' RACE experiments which revealed that some of these precursors are of unexpected length. The alignment of HYL1-dependent miRNA precursors to A. thaliana genomic sequences indicated the presence of introns in 12 out of 20 genes studied. Some of the characterized intron-containing pri-miRNAs undergo alternative splicing such as exon skipping or usage of alternative 5' splice sites suggesting that this process plays a role in the regulation of miRNA biogenesis. In the hyl1 mutant intron-containing pri-miRNAs accumulate alongside spliced pri-miRNAs suggesting the recruitment of HYL1 into the miRNA precursor maturation pathway before their splicing occurs.
authors.affiliation: Department of Gene Expression, Faculty of Biology, Institute of Molecular Biology and Biotechnology, Adam Mickiewicz University, Poznan, Poland.
authors.forename: Bogna
authors.initials: B
authors.lastname: Szarzynska
authors.forename: Lukasz
authors.initials: L
authors.lastname: Sobkowiak
authors.forename: Bikram Datt
authors.initials: BD
authors.lastname: Pant
authors.forename: Salma
authors.initials: S
authors.lastname: Balazadeh
authors.forename: Wolf-Rüdiger
authors.initials: WR
authors.lastname: Scheible
authors.forename: Bernd
authors.initials: B
authors.lastname: Mueller-Roeber
authors.forename: Artur
authors.initials: A
authors.lastname: Jarmolowski
authors.forename: Zofia
authors.initials: Z
authors.lastname: Szweykowska-Kulinska
mesh_terms: D017398:Alternative Splicing; D017360:Arabidopsis / Q000235:genetics* / Q000378:metabolism; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism*; D018506:Gene Expression Regulation, Plant; D017343:Genes, Plant; D007438:Introns; D035683:MicroRNAs / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D009154:Mutation; D012322:RNA Precursors / Q000737:chemistry / Q000378:metabolism; D012323:RNA Processing, Post-Transcriptional; D016601:RNA-Binding Proteins / Q000235:genetics / Q000378:metabolism*
chemical_list: D029681:Arabidopsis Proteins; C420966:HYL1 protein, Arabidopsis; D035683:MicroRNAs; D012322:RNA Precursors; D016601:RNA-Binding Proteins