Summary: Researchers have identified a direct connection between the protein p53 and autism-like behaviors in mice. By manipulating p53 levels specifically in the hippocampus, the team observed changes in social interaction, repetitive actions, and hippocampus-dependent learning and memory, revealing a notable role for the TP53 gene product in neurodevelopmental outcomes.
When hippocampal p53 was reduced, mice displayed more repetitive behaviors, diminished sociability, and weaker performance on tasks that rely on the hippocampus. These effects were particularly pronounced in male mice. The findings reveal a pathway by which p53 contributes to synaptic plasticity and behavior and help clarify links between gene regulation, synaptic function, and conditions such as autism spectrum disorder (ASD).
Key facts
- Lowering p53 levels in the hippocampus produced repetitive behaviors, reduced social interactions, and impaired hippocampus-dependent learning and memory in mice.
- p53 levels rose after active neuronal communication (long-term potentiation), a process associated with stronger learning and memory.
- Earlier work from 2018 implicated p53 in abnormal neuronal activity seen in both ASD and epilepsy, and the current study builds on that link.
Source: Beckman Institute
Overview of the findings
This study establishes p53 as a key regulator of social behavior, repetitive actions, and hippocampus-dependent learning and memory in mice, connecting the TP53 gene to neurodevelopmental and psychiatric features relevant to autism spectrum disorders. According to Nien-Pei Tsai, associate professor of molecular and integrative biology at the University of Illinois Urbana-Champaign and a researcher at the Beckman Institute, “This study shows for the first time that p53 is linked directly to autism-like behavior.”
Genes like TP53 encode proteins that control many aspects of cellular function. The TP53 gene encodes the p53 protein, which can act as a transcription factor to regulate expression of many genes. In neurons, activity-dependent transcription factors coordinate gene expression required for synaptic transmission and plasticity—processes fundamental to learning, memory, and behavior.
What the researchers did
Tsai and colleagues specifically reduced p53 expression in the forebrain and hippocampus of mice to observe behavioral and molecular consequences. They combined behavioral testing, electrophysiology, and molecular profiling to link changes in p53 with altered synaptic plasticity and gene expression patterns. The team also examined p53 dynamics in neurons after chemically induced long-term potentiation (cLTP), a laboratory model of the synaptic strengthening that underlies learning.
Major results
- Behavior: p53 knockdown increased repetitive behaviors and reduced sociability in both male and female mice, while not altering general locomotion or anxiety-like measures.
- Learning and memory: Mice with reduced p53 showed impaired hippocampal long-term potentiation and deficits in hippocampus-dependent learning and memory tasks. These learning deficits were stronger in male mice, indicating a possible sex-specific effect.
- Synaptic mechanisms: In cultured neurons, p53 levels rose after cLTP. Reducing p53 impaired the cLTP-induced increase of AMPA receptor subunits (GluA1 and GluA2) at the neuronal surface—molecular changes important for synaptic strengthening.
- Gene expression: RNA sequencing of the hippocampus revealed that p53 knockdown altered expression of multiple genes involved in synaptic plasticity and neurodevelopment, consistent with p53 acting as an activity-dependent transcription factor.
Interpretation and significance
Taken together, the data suggest p53 helps mediate activity-dependent synaptic strengthening by regulating AMPA receptor surface expression and transcription of plasticity-related genes. By supporting hippocampal synaptic plasticity, p53 appears to protect against autism-like behavioral features and to promote hippocampus-dependent learning and memory. The sex-dependent differences seen in learning outcomes highlight the importance of considering sex as a biological variable in studies of neurodevelopmental disorders.
Publication and authors
The study is reported in the paper titled “Tumor suppressor p53 modulates activity-dependent synapse strengthening, autism-like behavior and hippocampus-dependent learning,” published in the journal Molecular Psychiatry by Nien-Pei Tsai and colleagues.
Funding
This research was supported by the National Institutes of Health under award numbers R01NS105615, R01MH124827, and R21MH122840. The content reflects the authors’ findings and conclusions and does not necessarily represent the official views of the NIH.
About this genetics, ASD, and memory research news
Author: Jenna Kurtzweil
Source: Beckman Institute
Contact: Jenna Kurtzweil – Beckman Institute
Image: The image is credited to Neuroscience News
Original research: Closed access. “Tumor suppressor p53 modulates activity-dependent synapse strengthening, autism-like behavior and hippocampus-dependent learning” by Nien-Pei Tsai et al., Molecular Psychiatry.
Abstract (summary)
Synaptic potentiation depends on activity-dependent transcription factors that coordinate gene expression needed to sustain synaptic transmission. This study identifies the tumor suppressor p53 as a novel activity-dependent transcription factor that is elevated following chemically induced long-term potentiation. Knockdown experiments show that p53 is required for the cLTP-induced increase of AMPA receptor subunits at the neuronal surface. Forebrain-specific reduction of p53 promotes repetitive behavior and reduces sociability, while impairing hippocampal LTP and hippocampus-dependent learning and memory—effects that are more pronounced in male mice. RNA sequencing indicates that p53 knockdown alters genes with known roles in synaptic plasticity and neurodevelopment. Overall, the findings suggest p53 mediates AMPAR surface expression, supports hippocampal synaptic plasticity, suppresses autism-like behaviors, and promotes hippocampus-dependent learning and memory.