An important physiological control of the glycoprotein hormone a-subunit is the negative feedback by thyroid hormones in the thyrotrope. A region of the rat glycoprotein hormone a-subunit gene that is involved in transcriptional regulation by thyroid hormone has been identified by transient transfection studies, and sequence-specific binding of the thyroid hormone receptor to a site within this...

Facial morphometry using computerised image analysis was performed on patients with growth hormone receptor deficiency (Laron syndrome) from an inbred population of southern Ecuador. Morphometrics were compared for 49 patients, 70 unaffected relatives, and 14 unrelated persons. Patients with growth hormone receptor deficiency showed significant decreases in measures of vertical facial growth as...

Glycoprotein hormone receptors are G protein-coupled receptors with ligand-binding ectodomains consisting of leucine-rich repeats. The ectodomain is connected by a conserved cysteine-rich hinge region to the seven transmembrane (TM) region. Gain-of-function mutants of luteinizing hormone (LH) and thyroid-stimulating hormone receptors found in patients allowed identification of residues importan...

The cellular actions of the thyroid hormones L-thyroxine and L-triiodothyronine are mediated by the association of hormone with a chromatin-associated receptor. In cultured GH1 cells, a hormone-responsive rat pituitary cell line, thyroid hormone decreases the concentration of its receptor at early incubation times by reducing the accumulation of newly synthesized receptor. In this study, we dem...

The growth hormone receptor contains seven cysteine residues in its extracellular domain. The six in the growth hormone binding domain form disulfide bonds, and help the receptor to gain its correct three-dimensional structure. In this study we replaced the cysteine for serine and alanine residues and investigated their role in growth hormone receptor folding, dimerisation and signal transducti...

OBJECTIVE The aim of this study was to investigate the presence of growth hormone receptor in plexiform neurofibromas of neurofibromatosis type 1 patients. INTRODUCTION The development of multiple neurofibromas is one of the major features of neurofibromatosis type 1. Since neurofibromas commonly grow during periods of hormonal change, especially during puberty and pregnancy, it has been sugg...

Steroid hormone receptors activate specific gene transcription by binding as hormone-receptor complexes to short DNA enhancer-like elements termed hormone response elements. The DNA-binding domain (termed region C) is a highly conserved 66-amino acid region that contains two subregions (CI and CII) analogous to the "zinc fingers" of transcription factor IIIA. Using chimeric estrogen receptors, ...