title: Low-dose irradiation promotes Rad51 expression by down-regulating miR-193b-3p in hepatocytes.
abstract: Current evidence indicates that there is a relationship between microRNA (miRNA)-mediated gene silencing and low-dose irradiation (LDIR) responses. Here, alterations of miRNA expression in response to LDIR exposure in male BALB/c mice and three different types of hepatocytes were investigated. The miRNome of the LDIR-exposed mouse spleens (0.01 Gy, 6.5 mGy/h) was analyzed, and the expression of miRNA and mRNA was validated by qRT-PCR. Western blotting, chromatin immunoprecipitation (ChIP), and luciferase assays were also performed to evaluate the interaction between miRNAs and their target genes and to gain insight into the regulation of miRNA expression. The expression of miRNA-193b-3p was down-regulated in the mouse spleen and liver and in various hepatocytes (NCTC, Hepa, and HepG2 cell lines) in response to LDIR. The down-regulation of miR-193b-3p expression was caused by histone deacetylation on the miR-193b-3p promoter in the HepG2 cells irradiated with 0.01 Gy. However, the alteration of histone deacetylation and miR-193b-3p and Rad51 expression in response to LDIR was restored by pretreatment with N-acetyl-cyctein. In conclusion, we provide evidence that miRNA responses to LDIR include the modulation of cellular stress responses and repair mechanisms.
authors.affiliation: Research Center, Dongnam Institute of Radiological and Medical Science, 40 Jwadong-gil, Jangan-eup, Gijang-gun, Busan, 46033, Republic of Korea.
authors.forename: Eon-Seok
authors.initials: ES
authors.lastname: Lee
authors.affiliation: Research Center, Dongnam Institute of Radiological and Medical Science, 40 Jwadong-gil, Jangan-eup, Gijang-gun, Busan, 46033, Republic of Korea.
authors.forename: Yeo Jin
authors.initials: YJ
authors.lastname: Won
authors.affiliation: In silico Toxicology Research Center, Korea Insititute of Toxciology, Daejeon 305-343, Republic of Korea.
authors.forename: Byoung-Chul
authors.initials: BC
authors.lastname: Kim
authors.affiliation: In silico Toxicology Research Center, Korea Insititute of Toxciology, Daejeon 305-343, Republic of Korea.
authors.forename: Daeui
authors.initials: D
authors.lastname: Park
authors.affiliation: Research Center, Dongnam Institute of Radiological and Medical Science, 40 Jwadong-gil, Jangan-eup, Gijang-gun, Busan, 46033, Republic of Korea.
authors.forename: Jin-Han
authors.initials: JH
authors.lastname: Bae
authors.affiliation: Research Center, Dongnam Institute of Radiological and Medical Science, 40 Jwadong-gil, Jangan-eup, Gijang-gun, Busan, 46033, Republic of Korea.
authors.forename: Seong-Joon
authors.initials: SJ
authors.lastname: Park
authors.affiliation: Research Center, Dongnam Institute of Radiological and Medical Science, 40 Jwadong-gil, Jangan-eup, Gijang-gun, Busan, 46033, Republic of Korea.
authors.forename: Sung Jin
authors.initials: SJ
authors.lastname: Noh
authors.affiliation: Research Center, Dongnam Institute of Radiological and Medical Science, 40 Jwadong-gil, Jangan-eup, Gijang-gun, Busan, 46033, Republic of Korea.
authors.forename: Yeong-Rok
authors.initials: YR
authors.lastname: Kang
authors.affiliation: Research Center, Dongnam Institute of Radiological and Medical Science, 40 Jwadong-gil, Jangan-eup, Gijang-gun, Busan, 46033, Republic of Korea.
authors.forename: Si Ho
authors.initials: SH
authors.lastname: Choi
authors.affiliation: Department of Biochemistry and Molecular Biology, Medical University of South Carolina, Charleston, SC 29425, USA.
authors.forename: Je-Hyun
authors.initials: JH
authors.lastname: Yoon
authors.affiliation: Research Center, Dongnam Institute of Radiological and Medical Science, 40 Jwadong-gil, Jangan-eup, Gijang-gun, Busan, 46033, Republic of Korea.
authors.forename: Kyu
authors.initials: K
authors.lastname: Heo
authors.affiliation: Research Center, Dongnam Institute of Radiological and Medical Science, 40 Jwadong-gil, Jangan-eup, Gijang-gun, Busan, 46033, Republic of Korea.|Department of Radiation Oncology, Korea Institute of Radiological and Medical Sciences, Seoul 139-709, Republic of Korea.
authors.forename: Kwangmo
authors.initials: K
authors.lastname: Yang
authors.affiliation: Research Center, Dongnam Institute of Radiological and Medical Science, 40 Jwadong-gil, Jangan-eup, Gijang-gun, Busan, 46033, Republic of Korea.
authors.forename: Tae Gen
authors.initials: TG
authors.lastname: Son
mesh_terms: D000818:Animals; D002460:Cell Line; D045744:Cell Line, Tumor; D004249:DNA Damage; D004307:Dose-Response Relationship, Radiation; D015536:Down-Regulation / Q000528:radiation effects*; D020869:Gene Expression Profiling / Q000379:methods; D005786:Gene Expression Regulation / Q000528:radiation effects*; D045325:HCT116 Cells; D056945:Hep G2 Cells; D022781:Hepatocytes / Q000378:metabolism / Q000528:radiation effects*; D006801:Humans; D008297:Male; D008807:Mice, Inbred BALB C; D035683:MicroRNAs / Q000235:genetics*; D051135:Rad51 Recombinase / Q000235:genetics* / Q000378:metabolism
chemical_list: C568257:MIRN193 microRNA, mouse; D035683:MicroRNAs; D051135:Rad51 Recombinase; C495154:Rad51 protein, mouse