Protein Family: FGFR family, Receptor tyrosine kinase
FGFR-2 Protein
Overview
Fibroblast Growth Factor Receptor 2 (FGFR2) is a receptor tyrosine kinase that plays essential roles in embryonic development, tissue morphogenesis, and adult tissue homeostasis [1]. Like FGFR1, FGFR2 binds fibroblast growth factors but exhibits distinct ligand specificity, particularly for FGF7 and FGF10 (keratinocyte growth factor, KGF) [1]. In the nervous system, FGFR2 is expressed in neural progenitor cells, [astrocytes](/entities/astrocytes), and specific neuronal populations. FGFR2 signaling has been implicated in cortical development, hippocampal function, and neurodegenerative processes [2]. [@astrocyte2021]
Structure
FGFR2 shares structural homology with other FGFR family members, containing three immunoglobulin-like extracellular domains (IgI-IgIII), a transmembrane domain, and a split tyrosine kinase domain [1]. The receptor has multiple isoforms (FGFR2b, FGFR2c) generated by alternative splicing, with the FGFR2b isoform expressed primarily in epithelial cells and FGFR2c in mesenchymal cells [1]. This isoform diversity contributes to the tissue-specific functions of FGFR2. [@fgfkgf2020]
Normal Function
FGFR2 signaling is activated by a distinct set of FGF ligands compared to FGFR1, with particularly high affinity for FGF7 (KGF) and FGF10 [1]. In the nervous system: [@fgfr2018]
Cortical Development: FGFR2 regulates neural progenitor cell proliferation and differentiation during cortical development [2].
Astrocyte Function: FGFR2 is highly expressed in astrocytes and regulates their proliferation, survival, and function [3].
Hippocampal Neurogenesis: FGFR2 signaling contributes to adult hippocampal neurogenesis and cognitive function.
Olfactory System: FGFR2 plays a role in olfactory bulb development and function.
Wound Healing: In the CNS, FGFR2 activation promotes glial scar formation and tissue repair.
Role in Neurodegenerative Diseases
Alzheimer's Disease
FGFR2 is implicated in Alzheimer's disease pathogenesis:
Astrocyte Dysfunction: Altered FGFR2 signaling contributes to astrocyte reactivity and neuroinflammation in AD [3].
Amyloid Metabolism: FGF7/FGFR2 signaling may influence [amyloid precursor protein](/entities/app-protein) processing.
Neuronal Survival: FGFR2 provides trophic support to specific neuronal populations.
Parkinson's Disease
Dopaminergic Function: FGFR2 may modulate dopaminergic neuron survival and function.
Glial Responses: FGFR2 regulates microglial and astrocyte activation in PD models.
Other Neurological Conditions
Craniosynostosis: FGFR2 mutations cause premature skull suture fusion.
Atherosclerosis: FGFR2 in vascular cells affects cerebrovascular health.
Therapeutic Targeting
FGFR2-selective agonists: Targeting FGFR2-specific functions in the CNS.
FGF7/FGF10 analogs: KGF derivatives for neuroprotection.