Identification of an Enhancer Critical for the ephirn-A5 Gene Expression in the Posterior Region of the Mesencephalon
| Autor: | Soochul Park, Eunjeong Park, Hyuna Noh |
|---|---|
| Jazyk: | angličtina |
| Rok vydání: | 2017 |
| Předmět: |
0301 basic medicine
Electrophoretic Mobility Shift Assay Mice Transgenic Biology Article 03 medical and health sciences Transactivation Mice 0302 clinical medicine Genes Reporter Mesencephalon Gene expression Basic Helix-Loop-Helix Transcription Factors Animals Humans Electrophoretic mobility shift assay Binding site Enhancer Molecular Biology Transcription factor EphA Conserved Sequence Binding Sites Base Sequence Gene Expression Regulation Developmental Cell Biology General Medicine beta-Galactosidase Ephrin-A5 Introns Cell biology Mice Inbred C57BL ASCL1 030104 developmental biology bHLH transcription factor Enhancer Elements Genetic HEK293 Cells nervous system Cancer research Brain morphogenesis 030217 neurology & neurosurgery |
| Zdroj: | Molecules and Cells |
| ISSN: | 0219-1032 1016-8478 |
| Popis: | Ephrin-A5 has been implicated in the regulation of brain morphogenesis and axon pathfinding. In this study, we used bacterial homologous recombination to express a LacZ reporter in various ephrin-A5 BAC clones to identify elements that regulate ephrin-A5 gene expression during mesencephalon development. We found that there is mesencephalon-specific enhancer activity localized to a specific +25.0 kb to +30.5 kb genomic region in the first intron of ephrin-A5. Further comparative genomic analysis indicated that two evolutionary conserved regions, ECR1 and ECR2, were present within this 5.5 kb region. Deletion of ECR1 from the enhancer resulted in disrupted mesencephalon-specific enhancer activity in transgenic embryos. We also found a consensus binding site for basic helix-loop-helix (bHLH) transcription factors (TFs) in a highly conserved region at the 3'-end of ECR1. We further demonstrated that specific deletion of the bHLH TF binding site abrogated the mesencephalon-specific enhancer activity in transgenic embryos. Finally, both electrophoretic mobility shift assay and luciferase-based transactivation assay revealed that the transcription factor Ascl1 bound the bHLH consensus binding site in the mesencephalon-specific ephrin-A5 enhancer in vitro. Together, these results suggest that the bHLH TF binding site in ECR1 is involved in the positive regulation of ephrin-A5 gene expression during the development of the mesencephalon. |
| Databáze: | OpenAIRE |
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