Linking the environment, DAF-7/TGFβ signaling and LAG-2/DSL ligand expression in the germline stem cell niche
| Autor: | Maria C. Ow, E. Jane Albert Hubbard, Marcus B. Noyes, Kailyn Y. Hui, Olga Pekar, Sarah E. Hall |
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| Rok vydání: | 2016 |
| Předmět: |
0301 basic medicine
Chromatin Immunoprecipitation Notch signaling pathway Repressor SMAD Biology Germline 03 medical and health sciences 0302 clinical medicine Transforming Growth Factor beta medicine Animals Stem Cell Niche Caenorhabditis elegans Caenorhabditis elegans Proteins Molecular Biology In Situ Hybridization Genetics fungi Ligand (biochemistry) Stem Cells and Regeneration Cell biology 030104 developmental biology medicine.anatomical_structure Stem cell Signal transduction 030217 neurology & neurosurgery Germ cell Developmental Biology Signal Transduction |
| Zdroj: | Development (Cambridge, England). 144(16) |
| ISSN: | 1477-9129 |
| Popis: | The developmental accumulation of proliferative germ cells in the C. elegans hermaphrodite is sensitive to the organismal environment. Previously, we found that the TGFβ signaling pathway links the environment and proliferative germ cell accumulation. Neuronal DAF-7/TGFβ causes a DAF-1/TGFβR signaling cascade in the gonadal distal tip cell (DTC), the germline stem cell niche, where it negatively regulates a DAF-3 SMAD and DAF-5 Sno-Ski. LAG-2, a founding DSL ligand family member, is produced in the DTC and activates the GLP-1/Notch receptor on adjacent germ cells to maintain germline stem cell fate. Here, we show that DAF-7/TGFβ signaling promotes expression of lag-2 in the DTC in a daf-3-dependent manner. Using ChIP and one-hybrid assays, we find evidence for direct interaction between DAF-3 and the lag-2 promoter. We further identify a 25 bp DAF-3 binding element required for the DTC lag-2 reporter response to the environment and to DAF-7/TGFβ signaling. Our results implicate DAF-3 repressor complex activity as a key molecular mechanism whereby the environment influences DSL ligand expression in the niche to modulate developmental expansion of the germline stem cell pool. |
| Databáze: | OpenAIRE |
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