Filaggrin protein (FLG)

Filaggrin is an intermediate filament-associated structural protein crucial for epidermal differentiation and formation of the skin's protective barrier. Synthesized initially as profilaggrin—a large polyprotein stored in keratohyaline granules—filaggrin is proteolytically processed into functional monomers during terminal differentiation. These monomers aggregate keratin fibers within corneocytes, flattening cells and strengthening intercellular adhesion to create an effective physical barrier against water loss and environmental insults. Subsequent degradation yields hygroscopic amino acids that constitute natural moisturizing factors essential for maintaining hydration and acidic pH on the skin surface. Mutations leading to loss or reduction of functional filaggrin disrupt these processes, resulting in conditions like atopic dermatitis (eczema), ichthyosis vulgaris, increased asthma risk due to compromised epithelial integrity, and potential autoimmune cross-reactivity. While not itself a direct drug target currently, its genetic status serves as an important biomarker for several dermatological diseases[1][2][3][4][5].

Other names

Filament aggregating proteinFLGProfilaggrin (precursor form)