Folliculogenesis-specific basic helix-loop-helix transcription factor (FIGLA)

Folliculogenesis-specific basic helix-loop-helix transcription factor (FIGLA) is a germ cell–specific transcription factor essential for early stages of oogenesis and folliculogenesis in female mammals[1][2][3][4]. FIGLA activates transcription of oocyte-restricted genes, including those encoding the zona pellucida proteins (ZP1, ZP2, ZP3), and represses genes normally expressed in male germ cells[1][3]. This ensures proper formation of primordial follicles and promotes oocyte survival. FIGLA is a central node within a transcriptional regulatory network, interacting and co-regulating with other oocyte-specific factors such as NOBOX, LHX8, SOHLH1, and SOHLH2, to coordinate gene programs necessary for oocyte differentiation and ovarian reserve maintenance[2][4]. Disruption of FIGLA—by mutation or loss of expression—leads to impaired folliculogenesis, oocyte apoptosis, primordial follicle loss, and is associated with human reproductive disorders including premature ovarian failure[1][2][3][4]. FIGLA is highly conserved in vertebrates, indicating a fundamental role across species in early folliculogenesis[3][4]. There are currently no drugs targeting FIGLA directly, and no noted safety concerns specific to therapeutic targeting; however, its essential role in ovarian biology means any perturbation may carry a significant risk of infertility[1].

Other names

Factor in the germline alphaBHLHC8FIGalphabHLHc8FigalphaClass C basic helix-loop-helix protein 8Folliculogenesis-specific basic helix-loop-helix proteinTranscription factor FIGaPOF6