Transforming growth factor beta receptor 3-like protein (TGFBR3L)

Transforming growth factor beta receptor 3-like protein (TGFBR3L) is a type I transmembrane glycoprotein highly specific to pituitary gonadotrope cells in both humans and rodents, acting as a co-receptor for inhibin B[2][3][4]. TGFBR3L shares homology with the zona pellucida domain of betaglycan but is distinct in being highly enriched in and functionally restricted to the pituitary. It binds inhibin B with high affinity and specificity, thus mediating the antagonism of activin A signaling and the suppression of FSH production, playing a critical role in the regulation of female fertility[2][3][4]. Genetic studies in mice demonstrate that loss of TGFBR3L results in elevated FSH levels and enhanced fertility, highlighting its role as a physiological modulator of reproductive function. While expressed in normal and neoplastic gonadotrophs, it is not broadly expressed in other tissues and does not appear linked to primary clinical parameters such as age, sex, or tumor size, though it is associated with markers of gonadotroph differentiation and may influence pituitary tumor biology[3][4][5]. **Summary:** - TGFBR3L is a **gonadotroph-specific transmembrane receptor** and **inhibin B co-receptor** involved in *FSH regulation* and *female fertility*. - It is a **therapeutic target candidate** for endocrine and reproductive modulation, though no drugs are currently known to target it directly[2][3][4][5]. - Its expression may serve as a **biomarker** for gonadotroph cell differentiation and pituitary tumor subclassification[3][4].

Other names

TGFBR3LTransforming growth factor-beta receptor type 3-like proteinTGFR-3LTGF-beta receptor type III-like proteinGonadotroph enriched membrane protein (GEMP)TGF-beta receptor type-3-like proteinGEMP

Antagonism of activin A signaling via inhibin B binding. Regulation of FSH levels by mediating inhibin B’s suppressive effects on pituitary gonadotropes[2][3].