1:1 COMPLEX OF HUMAN GROWTH HORMONE MUTANT G120R WITH ITS SOLUBLE BINDING PROTEIN
[SOMA_HUMAN] Defects in GH1 are a cause of growth hormone deficiency isolated type 1A (IGHD1A) [MIM:262400]; also known as pituitary dwarfism I. IGHD1A is an autosomal recessive deficiency of GH which causes short stature. IGHD1A patients have an absence of GH with severe dwarfism and often develop anti-GH antibodies when given exogenous GH. Defects in GH1 are a cause of growth hormone deficiency isolated type 1B (IGHD1B) [MIM:612781]; also known as dwarfism of Sindh. IGHD1B is an autosomal recessive deficiency of GH which causes short stature. IGHD1B patients have low but detectable levels of GH. Dwarfism is less severe than in IGHD1A and patients usually respond well to exogenous GH. Defects in GH1 are the cause of Kowarski syndrome (KWKS) [MIM:262650]; also known as pituitary dwarfism VI.   Defects in GH1 are a cause of growth hormone deficiency isolated type 2 (IGHD2) [MIM:173100]. IGHD2 is an autosomal dominant deficiency of GH which causes short stature. Clinical severity is variable. Patients have a positive response and immunologic tolerance to growth hormone therapy. [GHR_HUMAN] Defects in GHR are a cause of Laron syndrome (LARS) [MIM:262500]. A severe form of growth hormone insensitivity characterized by growth impairment, short stature, dysfunctional growth hormone receptor, and failure to generate insulin-like growth factor I in response to growth hormone.          Defects in GHR may be a cause of idiopathic short stature autosomal (ISSA) [MIM:604271]. Short stature is defined by a subnormal rate of growth.
[SOMA_HUMAN] Plays an important role in growth control. Its major role in stimulating body growth is to stimulate the liver and other tissues to secrete IGF-1. It stimulates both the differentiation and proliferation of myoblasts. It also stimulates amino acid uptake and protein synthesis in muscle and other tissues. [GHR_HUMAN] Receptor for pituitary gland growth hormone involved in regulating postnatal body growth. On ligand binding, couples to the JAK2/STAT5 pathway (By similarity). The soluble form (GHBP) acts as a reservoir of growth hormone in plasma and may be a modulator/inhibitor of GH signaling. Isoform 2 up-regulates the production of GHBP and acts as a negative inhibitor of GH signaling.
Publication Abstract from PubMed
Human growth hormone binds two receptor molecules and thereby induces signal transduction through receptor dimerization. At high concentrations, growth hormone acts as an antagonist because of a large difference in affinities at the respective binding sites. This antagonist action can be enhanced further by reducing binding in the low affinity binding site. A growth hormone antagonist mutant Gly-120 --> Arg, has been crystallized with its receptor as a 1:1 complex and the crystal structure determined at 2.9 A resolution. The 1:1 complex is remarkably similar to the native growth hormone-receptor 1:2 complex. A comparison between the two structures reveals only minimal differences in the conformations of the hormone or its receptor in the two complexes, including the angle between the two immunoglobulin-like domains of the receptor. Further, two symmetry-related 1:1 complexes in the crystal form a 2:2 complex with a large solvent inaccessible area between two receptor molecules. In addition, we present here a native human growth hormone-human growth hormone-binding protein 1:2 complex structure at 2.5 A resolution. One important difference between our structure and the previously published crystal structure at 2.8 A is revealed. Trp-104 in the receptor, a key residue in the hormone-receptor interaction, has an altered conformation in the low affinity site enabling a favorable hydrogen bond to be formed with Asp-116 of the hormone.
Crystal structure of an antagonist mutant of human growth hormone, G120R, in complex with its receptor at 2.9 A resolution.,Sundstrom M, Lundqvist T, Rodin J, Giebel LB, Milligan D, Norstedt G J Biol Chem. 1996 Dec 13;271(50):32197-203. PMID:8943276
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.