Functional characterization of two naturally occurring mutations V 221 G and T 449 N in the follicle stimulating hormone receptor

Mol Cell Endocrinol. 2017 Jan 15;440:69-79. doi: 10.1016/j.mce.2016.11.020. Epub 2016 Nov 23.

Abstract

Naturally occurring mutations in follicle stimulating hormone receptor (FSHR) affect the receptor function. Here, we characterized two such previously reported mutations, V221G and T449N, in the extracellular domain and transmembrane helix 3, of FSHR, respectively. Functional studies with the V221G mutant demonstrated an impairment in FSH binding and signaling. Validation of X-ray crystallography data indicating the contribution of FSHR specific residues in the vicinity of V221 to contribute to FSH-FSHR interaction was carried out. In vitro mutational studies showed that these residues are determinants of both FSH binding and FSH induced signaling. Analysis of the T449N mutation revealed that it results in an increase in FSH binding and high cAMP response at lower doses of FSH. A marginal hCG induced and no TSH induced cAMP production was also observed. These findings corroborated with the clinical manifestations of primary amenorrhea (V221G) and spontaneous ovarian hyperstimulation syndrome (T449N) in women harbouring these mutations.

Keywords: Extracellular domain; FSH receptor; Naturally occurring mutations; Ovarian hyperstimulation syndrome; Primary amenorrhea.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • CHO Cells
  • Cell Membrane / metabolism
  • Chorionic Gonadotropin / pharmacology
  • Cricetinae
  • Cricetulus
  • Crystallography, X-Ray
  • Cyclic AMP / metabolism
  • DNA Mutational Analysis
  • Endocytosis
  • Female
  • Follicle Stimulating Hormone / metabolism
  • Humans
  • Imaging, Three-Dimensional
  • Luteinizing Hormone / pharmacology
  • Point Mutation / genetics*
  • Receptors, FSH / genetics*
  • Receptors, FSH / metabolism
  • Thyrotropin / pharmacology

Substances

  • Chorionic Gonadotropin
  • Receptors, FSH
  • Luteinizing Hormone
  • Follicle Stimulating Hormone
  • Thyrotropin
  • Cyclic AMP