Alterations in the expression, structure and function of progesterone receptor membrane component-1 (PGRMC1) in premature ovarian failure

Hum Mol Genet. 2008 Dec 1;17(23):3776-83. doi: 10.1093/hmg/ddn274. Epub 2008 Sep 9.

Abstract

Premature ovarian failure (POF) is characterized by hypergonadotropic hypogonadism and amenorrhea before the age of 40. The condition has a heterogeneous background but genetic factors are demonstrated by the occurrence of familial cases. We identified a mother and daughter with POF both of whom carry an X;autosome translocation [t(X;11)(q24;q13)]. RNA expression studies of genes flanking the X-chromosome breakpoint revealed that both patients have reduced expression levels of the gene Progesterone Receptor Membrane Component-1 (PGRMC1). Mutation screening of 67 females with idiopathic POF identified a third patient with a missense mutation (H165R) located in the cytochrome b5 domain of PGRMC1. PGRMC1 mediates the anti-apoptotic action of progesterone in ovarian cells and it acts as a positive regulator of several cytochrome P450 (CYP)-catalyzed reactions. The CYPs are critical for intracellular sterol metabolism, including biosynthesis of steroid hormones. We show that the H165R mutation associated with POF abolishes the binding of cytochrome P450 7A1 (CYP7A1) to PGRMC1. In addition, the missense mutation attenuates PGRMC1's ability to mediate the anti-apoptotic action of progesterone in ovarian cells. These findings suggest that mutant or reduced levels of PGMRC1 may cause POF through impaired activation of the microsomal cytochrome P450 and increased apoptosis of ovarian cells.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Adolescent
  • Adult
  • Apoptosis
  • Chromosomes, Human, X / genetics
  • Cytochrome P-450 Enzyme System / genetics
  • Cytochrome P-450 Enzyme System / metabolism
  • DNA Methylation
  • Female
  • Gene Expression*
  • Humans
  • Membrane Proteins / chemistry*
  • Membrane Proteins / genetics
  • Membrane Proteins / metabolism*
  • Mutation, Missense
  • Primary Ovarian Insufficiency / genetics*
  • Primary Ovarian Insufficiency / metabolism
  • Primary Ovarian Insufficiency / physiopathology
  • Protein Structure, Tertiary
  • Receptors, Progesterone / chemistry*
  • Receptors, Progesterone / genetics
  • Receptors, Progesterone / metabolism*
  • Translocation, Genetic
  • Young Adult

Substances

  • Membrane Proteins
  • PGRMC1 protein, human
  • Receptors, Progesterone
  • Cytochrome P-450 Enzyme System