Htr2A is an important component in the neurobiology of neurodegenerative diseases. This page provides detailed information about its structure, function, and role in disease processes.
Serotonin receptor implicated in neuropsychiatric disorders
The HTR2A gene (5-Hydroxytryptamine Receptor 2A) is located on chromosome 13q14 and encodes a protein involved in G protein-coupled receptor signaling. This gene has been implicated in several neurodegenerative diseases and neuropsychiatric disorders.
| Attribute | Value |
|---|---|
| Symbol | HTR2A |
| Full Name | 5-Hydroxytryptamine Receptor 2A |
| Chromosomal Location | 13q14 |
| NCBI Gene ID | 3355 |
| OMIM | 182134 |
| Ensembl ID | ENSG00000102468 |
| UniProt ID | P28223 |
The HTR2A gene encodes the 5-HT2A receptor, a Gq-coupled GPCR highly expressed in cortical pyramidal neurons. This receptor mediates psychedelic experiences, regulates mood, cognition, and perception. In Alzheimer's disease, 5-HT2A receptor density is reduced in the cortex, correlating with cognitive deficits and psychotic symptoms. The receptor plays important roles in NMDA receptor-dependent synaptic plasticity, long-term potentiation, and memory consolidation. In Parkinson's disease, 5-HT2A dysregulation contributes to levodopa-induced psychosis and hallucinations.
The HTR2A gene has been linked to the following diseases:
Highest expression in layer 5 pyramidal neurons of prefrontal cortex, primary somatosensory cortex, and motor cortex. Also expressed in hippocampus (pyramidal cells), basal ganglia, and thalamus. Lower expression in brainstem raphe nuclei (presynaptic autoreceptors).
5-HT2A antagonists (risperidone, pimavanserin) are used for schizophrenia and Parkinson's disease psychosis. Pimavanserin (Nuplazid) is FDA-approved for PD psychosis. Classic hallucinogens (psilocybin, LSD) act as 5-HT2A agonists - being investigated for treatment-resistant depression. 5-HT2A inverse agonists (nelotanserin) in clinical trials for Lewy body dementia.
The study of Htr2A has evolved significantly over the past decades. Research in this area has revealed important insights into the underlying mechanisms of neurodegeneration and continues to drive therapeutic development.
Historical context and key discoveries in this field have shaped our current understanding and will continue to guide future research directions.
The HTR2A gene spans approximately 63 kb on chromosome 13q14 and consists of 3 exons encoding a 471 amino acid protein. The gene has a typical GPCR structure with:
Several splice variants have been identified, including:
| Trial | Drug | Phase | Status | Indication |
|---|---|---|---|---|
| NCT02847650 | Pimavanserin | Phase 3 | Completed | Parkinson's Disease Psychosis |
| NCT03149783 | Nelotanserin | Phase 2 | Completed | Lewy Body Dementia |
| NCT03429075 | PF-06412562 | Phase 1 | Completed | Schizophrenia |