Agrin-Lrp4-Ror2 signaling regulates adult hippocampal neurogenesis in mice
Abstract
Adult neurogenesis in the hippocampus may represent a form of plasticity in brain functions including mood, learning and memory. However, mechanisms underlying neural stem/progenitor cells (NSPCs) proliferation are not well understood. We found that Agrin, a factor critical for neuromuscular junction formation, is elevated in the hippocampus of mice that are stimulated by enriched environment (EE). Genetic deletion of the Agrn gene in excitatory neurons decreases NSPCs proliferation and increases depressing-like behavior. Low-density lipoprotein receptor-related protein 4 (Lrp4), a receptor for Agrin, is expressed in hippocampal NSPCs and its mutation blocked basal as well as EE-induced NSPCs proliferation and maturation of newborn neurons. Finally, we show that Lrp4 interacts with and activates receptor tyrosine kinase-like orphan receptor 2 (Ror2); and Ror2 mutation impairs NSPCs proliferation. Together, these observations identify a role of Agrin-Lrp4-Ror2 signaling for adult neurogenesis, uncovering previously unexpected functions of Agrin and Lrp4 in the brain.
Data availability
All data generated or analysed during this study are included in the manuscript and supporting files.
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Author details
Funding
National Institutes of Health (MH083317)
- Lin Mei
National Institutes of Health (MH109280)
- Lin Mei
National Institutes of Health (NS082007)
- Lin Mei
National Institutes of Health (NS090083)
- Lin Mei
National Institutes of Health (AG051510)
- Lin Mei
National Institutes of Health (AG051773)
- Wen-Cheng Xiong
National Institutes of Health (AG045781)
- Wen-Cheng Xiong
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Ethics
Animal experimentation: All procedures involving animals were in accordance with the National Institutes of Health Guide for the care and use of Laboratory Animals and approved by Institutional Animal Care and Use Committees of Augusta University (Protocol #: 2011-0393) and Case Western Reserve University (Protocol #: 2017-0115).
Copyright
© 2019, Zhang et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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