title: MicroRNA-7a regulates Müller glia differentiation by attenuating Notch3 expression.
abstract: miRNA-7a plays critical roles in various biological aspects in health and disease. We aimed to reveal roles of miR-7a in mouse retinal development by loss- and gain-of-function analyses of miR-7a. Plasmids encoding miR-7a or miR-7a-decoy (anti-sense miR-7a) were introduced into mouse retina at P0, and the retina was cultured as explant. Then, proliferation of retinal progenitors and differentiation of retinal subtypes were examined by immunostaining. miR-7a had no apparent effect on the proliferation of retinal progenitor cells. However, the expression of Müller glia marker, cyclin D3, was reduced by miR-7a overexpression and up-regulated by miR-7a decoy, suggesting that miR-7a negatively regulates differentiation of Müller glia. Targets of miR-7a, which were predicted by using a public program miRNA.org, and Notch3 was suggested to be one of candidate genes of miR-7a target. Notch3 3' UTR appeared to contain complementary sequence to the seed sequence of miR-7a. A reporter assay in NIH3T3 cells using a plasmid containing multiple repeats of potential target sequence of 3' Notch UTR showed that miR-7a suppress expression of reporter EGFP through 3'UTR region. Expression of sh-Notch3 and over-expression of NICD3 in retina suggested that miR-7a regulates Müller glia differentiation through attenuation of Notch3 expression. Taken together, we revealed that the miR-7a regulates the differentiation of Müller glia through the suppression of Notch3 expression.
authors.affiliation: Division of Molecular and Developmental Biology, Institute of Medical Science, University of Tokyo, Tokyo, Japan.
authors.forename: Yukihiro
authors.initials: Y
authors.lastname: Baba
authors.affiliation: Division of Molecular and Developmental Biology, Institute of Medical Science, University of Tokyo, Tokyo, Japan.
authors.forename: Yuko
authors.initials: Y
authors.lastname: Aihara
authors.affiliation: Division of Molecular and Developmental Biology, Institute of Medical Science, University of Tokyo, Tokyo, Japan. Electronic address: sumiko@ims.u-tokyo.ac.jp.
authors.forename: Sumiko
authors.initials: S
authors.lastname: Watanabe
mesh_terms: D000818:Animals; D015415:Biomarkers / Q000378:metabolism; D002454:Cell Differentiation / Q000502:physiology*; D049109:Cell Proliferation; D018274:Electroporation; D063928:Ependymoglial Cells / Q000166:cytology*; D015870:Gene Expression / Q000502:physiology; D007150:Immunohistochemistry; D051379:Mice; D008813:Mice, Inbred ICR; D035683:MicroRNAs / Q000502:physiology*; D041681:NIH 3T3 Cells; D009924:Organ Culture Techniques; D010957:Plasmids; D060888:Real-Time Polymerase Chain Reaction; D000071656:Receptor, Notch3; D051880:Receptors, Notch / Q000235:genetics* / Q000378:metabolism; D014162:Transfection
chemical_list: D015415:Biomarkers; C549243:MIRN7 microRNA, mouse; D035683:MicroRNAs; C499373:Notch3 protein, mouse; D000071656:Receptor, Notch3; D051880:Receptors, Notch
keywords: Explant culture; Mouse; Mueller glia; Notch; miRNA