ADGRB1 contributes to astrocyte-mediated phagocytosis of excitatory synapses
Ontology highlight
ABSTRACT:
PROVIDER: PRJNA1073438 | ENA |
REPOSITORIES: ENA
Dataset's files
| Action | DRS | |||
|---|---|---|---|---|
| SRR27871792_1.fastq.gz | Fastqsanger.gz | |||
| SRR27871792_2.fastq.gz | Fastqsanger.gz | |||
| SRR27871793_1.fastq.gz | Fastqsanger.gz | |||
| SRR27871793_2.fastq.gz | Fastqsanger.gz | |||
| SRR27871794_1.fastq.gz | Fastqsanger.gz |
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Project description:Excitatory synapses occur mainly on dendritic spines, and spine density is usually correlated with the strength of excitatory synaptic transmission. We report that Nr4a1, an activity-inducible gene encoding a nuclear receptor, regulates the density and distribution of dendritic spines in CA1 pyramidal neurons. Nr4a1 overexpression resulted in elimination of the majority of spines; however, postsynaptic densities were preserved on dendritic shafts, and the strength of excitatory synaptic transmission was unaffected, showing that excitatory synapses can be dissociated from spines. mRNA expression profiling studies suggest that Nr4a1-mediated transcriptional regulation of the actin cytoskeleton contributes to this effect. Under conditions of chronically elevated activity, when Nr4a1 was induced, Nr4a1 knockdown increased the density of spines and PSDs specifically at the distal ends of dendrites. Thus, Nr4a1 is a key component of an activity-induced transcriptional program that regulates the density and distribution of spines and synapses. After 10 days in culture, dissociated mouse hippocampal neurons in 6-well plates were infected with lentivirus expressing either Flag-Nr4a1 or GFP and incubated for 6 days to allow for transgene expression. Total RNA was then isolated using RNeasy Plus kit (QIAGEN). Samples passing an mRNA quality check proceeded to quantitative analysis on Agilent-026655 4x44 Mouse Microarrays.
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