title: MicroRNA 340 is involved in UVB-induced dendrite formation through the regulation of RhoA expression in melanocytes.
abstract: The influence of UV irradiation on pigmentation is well established, but the molecular and cellular mechanisms controlling dendrite formation remain incompletely understood. MicroRNAs (miRNAs) are a class of small RNAs that participate in various cellular processes by suppressing the expression of target mRNAs. In this study, we investigated the expression of miRNAs in response to UVB irradiation using a microarray screen and then identified potential mRNA targets for differentially expressed miRNAs among the genes governing dendrite formation. We subsequently determined the ability of miRNA 340 (miR-340) to suppress the expression of RhoA, which is a predicted miR-340 target gene that regulates dendrite formation. The overexpression of miR-340 promoted dendrite formation and melanosome transport, and the downregulation of miR-340 inhibited UVB-induced dendrite formation and melanosome transport. Moreover, a luciferase reporter assay demonstrated direct targeting of RhoA by miR-340 in the immortalized human melanocyte cell line Pig1. In conclusion, this study has established an miRNA associated with UVB irradiation. The significant downregulation of RhoA protein and mRNA expression after UVB irradiation and the modulation of miR-340 expression suggest a key role for miR-340 in regulating UVB-induced dendrite formation and melanosome transport.
authors: Department of Dermatology, Xijing Hospital, Fourth Military Medical University, Xi'an, China.
authors: Qiang
authors: Q
authors: Jian
authors: Department of Dermatology, Xijing Hospital, Fourth Military Medical University, Xi'an, China.
authors: Qing
authors: Q
authors: An
authors: Department of Dermatology, Xijing Hospital, Fourth Military Medical University, Xi'an, China.
authors: Dongning
authors: D
authors: Zhu
authors: Department of Dermatology, Xijing Hospital, Fourth Military Medical University, Xi'an, China Department of Dermatology, Shaanxi Provincial Hospital of Traditional Chinese Medicine, Xi'an, China.
authors: Kun
authors: K
authors: Hui
authors: Department of Dermatology, Xijing Hospital, Fourth Military Medical University, Xi'an, China.
authors: Ying
authors: Y
authors: Liu
authors: Department of Physiology, Fourth Military Medical University, Xi'an, China chxinli@fmu.edu.cn chengxinderm@163.com.
authors: Sumin
authors: S
authors: Chi
authors: Department of Dermatology, Xijing Hospital, Fourth Military Medical University, Xi'an, China Department of Dermatology, Chinese People's Liberation Army General Hospital, Beijing, China chxinli@fmu.edu.cn chengxinderm@163.com.
authors: Chengxin
authors: C
authors: Li
mesh_terms: D001483:Base Sequence; D001665:Binding Sites; D002460:Cell Line; D003712:Dendrites / Q000378:metabolism / Q000528:radiation effects*; D005786:Gene Expression Regulation / Q000528:radiation effects*; D006801:Humans; D008544:Melanocytes / Q000502:physiology / Q000528:radiation effects*; D035683:MicroRNAs / Q000235:genetics*; D008969:Molecular Sequence Data; D020411:Oligonucleotide Array Sequence Analysis; D012333:RNA, Messenger / Q000235:genetics; D016415:Sequence Alignment; D012880:Skin Pigmentation / Q000235:genetics / Q000502:physiology; D020764:cdc42 GTP-Binding Protein / Q000378:metabolism; D054460:rho-Associated Kinases / Q000378:metabolism; D020742:rhoA GTP-Binding Protein / Q000235:genetics / Q000378:metabolism
chemical_list: C570046:MIRN340 microRNA, human; D035683:MicroRNAs; D012333:RNA, Messenger; C515851:ROCK1 protein, human; D054460:rho-Associated Kinases; D020764:cdc42 GTP-Binding Protein; D020742:rhoA GTP-Binding Protein