Protein Family: FGFR family, Receptor tyrosine kinase
FGFR-1 Protein
Overview
Fibroblast Growth Factor Receptor 1 (FGFR1) is a receptor tyrosine kinase that plays critical roles in neuronal development, survival, and plasticity. As part of the FGFR family, FGFR1 binds fibroblast growth factors (FGFs) to activate downstream signaling pathways including RAS/MAPK, PI3K/AKT, and PLCG [1]. In the central nervous system, FGFR1 is essential for neurogenesis, neural stem cell maintenance, and synaptic plasticity [1]. Dysregulation of FGFR1 signaling has been implicated in Alzheimer's disease, Parkinson's disease, and various neuropsychiatric disorders [2][3]. [@fibroblast2020]
Structure
FGFR1 is a single-pass transmembrane receptor composed of an extracellular ligand-binding domain with three immunoglobulin-like domains (IgI-IgIII), a transmembrane helix, and an intracellular tyrosine kinase domain [1]. The receptor exists in multiple splice isoforms (FGFR1b, FGFR1c) with distinct ligand affinities. Upon FGF binding to the extracellular domain, FGFR1 dimerizes and undergoes autophosphorylation, activating its intracellular tyrosine kinase activity. Structural studies have revealed the molecular basis for FGF-FGFR interactions, with the Ig2 and Ig3 domains mediating ligand binding specificity. [@fgffgfr2021]
Normal Function
FGFR1 signaling is activated by multiple FGF ligands including FGF1 (acidic FGF), FGF2 (basic FGF), FGF4, and others [1]. In the nervous system: [@fgfr2018]
Neural Development: FGFR1 is expressed in neural stem cells and progenitor cells, where it promotes proliferation, differentiation, and survival during brain development [4].
Neurogenesis: FGFR1 signaling maintains adult hippocampal neurogenesis and supports neural progenitor cell pools in the subventricular zone [4].
Synaptic Plasticity: FGFR1 is present at synapses and modulates glutamatergic signaling, [long-term potentiation](/mechanisms/long-term-potentiation) (LTP), and learning and memory [5].
Astrocyte Function: FGFR1 regulates astrocyte proliferation and function, important for neuronal support and metabolism.
Neuroprotection: FGFR1 activation can protect [neurons](/entities/neurons) from various insults including oxidative stress and excitotoxicity [2].
Role in Neurodegenerative Diseases
Alzheimer's Disease
FGFR1 signaling is implicated in Alzheimer's disease through multiple mechanisms: [@therapeutic2021]
[Amyloid-beta](/proteins/amyloid-beta) toxicity: FGF2/FGFR1 signaling can protect against amyloid-beta-induced neuronal death [2][5].
[Tau](/proteins/tau) pathology: FGFR1 activation may influence tau phosphorylation and aggregation.
Synaptic dysfunction: Altered FGFR1 signaling contributes to synaptic loss in AD [5].
Neuroinflammation: FGFR1 modulates glial activation and neuroinflammatory responses.
Parkinson's Disease
In PD, FGFR1 plays complex roles: [@fgfr2019a]
Dopaminergic neuron survival: FGFR1 agonists have shown neuroprotective effects on dopaminergic neurons [3].
[Alpha-synuclein](/proteins/alpha-synuclein) pathology: FGFR1 signaling may influence alpha-synuclein aggregation and toxicity.
Mitochondrial function: FGFR1 activation can improve mitochondrial function under stress.
Other Neurological Conditions
Depression: FGFR1 signaling is implicated in hippocampal neurogenesis and antidepressant efficacy [7].
Stroke: FGFR1 activation promotes neural repair and functional recovery after stroke.