title: Characterization of microRNAs and their target genes associated with transcriptomic changes in gamma-irradiated Arabidopsis.
abstract: MicroRNAs (miRNAs) regulate gene expression in response to biotic and abiotic stress in plants. We investigated gamma-ray-responsive miRNAs in Arabidopsis wild-type and cmt3-11t mutant plants using miRNA microarray analysis. miRNA expression was differentiated between the wild-type and cmt3-11t mutants. miR164a, miR169d, miR169h, miR172b*, and miR403 were identified as repressible in the wild-type and/or cmt3-11t mutant in response to gamma irradiation, while miR827, miR840, and miR850 were strongly inducible. These eight miRNA genes contain UV-B-responsive cis-elements, including G-box, I-box core, ARE, and/or MBS in the putative promoter regions. Moreover, Box 4, MBS, TCA-element, and Unnamed_4, as well as CAAT- and TATA-box, were identified in these eight miRNA genes. However, a positive correlation between the transcriptions of miRNAs and their putative target genes was only observed between miR169d and At1g30560 in the wild-type, and between miR827 and At1g70700 in the cmt3-11t mutant. Quantitative RT-PCR analysis confirmed that the transcription of miR164a, miR169d, miR169h, miR172b*, miR403, and miR827 differed after gamma irradiation depending on the genotype (wild-type, cmt3-11t, drm2, drd1-6, and ddm1-2) and developmental stage (14 or 28 days after sowing). In contrast, high transcriptional induction of miR840 and miR850 was observed in these six genotypes regardless of the developmental stage. Although the actual target genes and functions of miR840 and miR850 remain to be determined, our results indicate that these two miRNAs may be strongly induced and reproducible genetic markers in Arabidopsis plants exposed to gamma rays.
authors.affiliation: Advanced Radiation Technology Institute, Korea Atomic Energy Research Institute, Jeongeup-si, Jeollabuk-do, Republic of Korea jhongkim@kaeri.re.kr.|Department of Radiation Biotechnology and Applied Radioisotope Science, University of Science and Technology, Yuseong-gu, Daejeon, Republic of Korea jhongkim@kaeri.re.kr.
authors.forename: J H
authors.initials: JH
authors.lastname: Kim
authors.affiliation: Advanced Radiation Technology Institute, Korea Atomic Energy Research Institute, Jeongeup-si, Jeollabuk-do, Republic of Korea.
authors.forename: Y S
authors.initials: YS
authors.lastname: Go
authors.affiliation: Advanced Radiation Technology Institute, Korea Atomic Energy Research Institute, Jeongeup-si, Jeollabuk-do, Republic of Korea.
authors.forename: J K
authors.initials: JK
authors.lastname: Kim
authors.affiliation: Advanced Radiation Technology Institute, Korea Atomic Energy Research Institute, Jeongeup-si, Jeollabuk-do, Republic of Korea.
authors.forename: B Y
authors.initials: BY
authors.lastname: Chung
mesh_terms: D017360:Arabidopsis / Q000235:genetics* / Q000378:metabolism / Q000528:radiation effects; D029681:Arabidopsis Proteins / Q000235:genetics* / Q000378:metabolism; D019175:DNA Methylation; D044127:Epigenesis, Genetic; D005720:Gamma Rays; D018506:Gene Expression Regulation, Plant; D035683:MicroRNAs / Q000235:genetics* / Q000378:metabolism; D011401:Promoter Regions, Genetic; D018749:RNA, Plant / Q000235:genetics / Q000378:metabolism; D036226:Seedlings / Q000235:genetics / Q000378:metabolism / Q000528:radiation effects; D017422:Sequence Analysis, DNA; D013312:Stress, Physiological; D059467:Transcriptome / Q000528:radiation effects*
chemical_list: D029681:Arabidopsis Proteins; D035683:MicroRNAs; D018749:RNA, Plant