title: Identification and characterization of FGF2-dependent mRNA: microRNA networks during lens fiber cell differentiation.
abstract: MicroRNAs (miRNAs) and fibroblast growth factor (FGF) signaling regulate a wide range of cellular functions, including cell specification, proliferation, migration, differentiation, and survival. In lens, both these systems control lens fiber cell differentiation; however, a possible link between these processes remains to be examined. Herein, the functional requirement for miRNAs in differentiating lens fiber cells was demonstrated via conditional inactivation of Dicer1 in mouse (Mus musculus) lens. To dissect the miRNA-dependent pathways during lens differentiation, we used a rat (Rattus norvegicus) lens epithelial explant system, induced by FGF2 to differentiate, followed by mRNA and miRNA expression profiling. Transcriptome and miRNome analysis identified extensive FGF2-regulated cellular responses that were both independent and dependent on miRNAs. We identified 131 FGF2-regulated miRNAs. Seventy-six of these miRNAs had at least two in silico predicted and inversely regulated target mRNAs. Genes modulated by the greatest number of FGF-regulated miRNAs include DNA-binding transcription factors Nfib, Nfat5/OREBP, c-Maf, Ets1, and N-Myc. Activated FGF signaling influenced bone morphogenetic factor/transforming growth factor-β, Notch, and Wnt signaling cascades implicated earlier in lens differentiation. Specific miRNA:mRNA interaction networks were predicted for c-Maf, N-Myc, and Nfib (DNA-binding transcription factors); Cnot6, Cpsf6, Dicer1, and Tnrc6b (RNA to miRNA processing); and Ash1l, Med1/PBP, and Kdm5b/Jarid1b/Plu1 (chromatin remodeling). Three miRNAs, including miR-143, miR-155, and miR-301a, down-regulated expression of c-Maf in the 3'-UTR luciferase reporter assays. These present studies demonstrate for the first time global impact of activated FGF signaling in lens cell culture system and predicted novel gene regulatory networks connected by multiple miRNAs that regulate lens differentiation.
authors.affiliation: Department of Genetics, Albert Einstein College of Medicine, Bronx, New York 10461.
authors.forename: Louise
authors.initials: L
authors.lastname: Wolf
authors.forename: Chun S
authors.initials: CS
authors.lastname: Gao
authors.forename: Karen
authors.initials: K
authors.lastname: Gueta
authors.forename: Qing
authors.initials: Q
authors.lastname: Xie
authors.forename: Tiphaine
authors.initials: T
authors.lastname: Chevallier
authors.forename: Nikhil R
authors.initials: NR
authors.lastname: Podduturi
authors.forename: Jian
authors.initials: J
authors.lastname: Sun
authors.forename: Ivan
authors.initials: I
authors.lastname: Conte
authors.forename: Peggy S
authors.initials: PS
authors.lastname: Zelenka
authors.forename: Ruth
authors.initials: R
authors.lastname: Ashery-Padan
authors.forename: Jiri
authors.initials: J
authors.lastname: Zavadil
authors.forename: Ales
authors.initials: A
authors.lastname: Cvekl
mesh_terms: D000818:Animals; D059447:Cell Cycle Checkpoints / Q000235:genetics; D002454:Cell Differentiation / Q000235:genetics*; D002478:Cells, Cultured; D053487:DEAD-box RNA Helicases / Q000235:genetics; D005260:Female; D016222:Fibroblast Growth Factor 2 / Q000235:genetics* / Q000378:metabolism / Q000494:pharmacology; D020869:Gene Expression Profiling; D053263:Gene Regulatory Networks; D066298:In Vitro Techniques; D007908:Lens, Crystalline / Q000002:abnormalities / Q000166:cytology* / Q000187:drug effects / Q000502:physiology; D051379:Mice; D008817:Mice, Mutant Strains; D035683:MicroRNAs / Q000378:metabolism*; D011247:Pregnancy; D012333:RNA, Messenger / Q000378:metabolism; D051381:Rats; D043244:Ribonuclease III / Q000235:genetics; D059467:Transcriptome
chemical_list: D035683:MicroRNAs; D012333:RNA, Messenger; D016222:Fibroblast Growth Factor 2; C509781:Dicer1 protein, mouse; D043244:Ribonuclease III; D053487:DEAD-box RNA Helicases
keywords: Dicer1; FGF2; c-Maf; differentiation; lens; microRNAs; signaling