HUMAN GROWTH HORMONE AND EXTRACELLULAR DOMAIN OF ITS RECEPTOR: CRYSTAL STRUCTURE OF THE COMPLEX
[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
Binding of human growth hormone (hGH) to its receptor is required for regulation of normal human growth and development. Examination of the 2.8 angstrom crystal structure of the complex between the hormone and the extracellular domain of its receptor (hGHbp) showed that the complex consists of one molecule of growth hormone per two molecules of receptor. The hormone is a four-helix bundle with an unusual topology. The binding protein contains two distinct domains, similar in some respects to immunoglobulin domains. The relative orientation of these domains differs from that found between constant and variable domains in immunoglobulin Fab fragments. Both hGHbp domains contribute residues that participate in hGH binding. In the complex both receptors donate essentially the same residues to interact with the hormone, even though the two binding sites on hGH have no structural similarity. Generally, the hormone-receptor interfaces match those identified by previous mutational analyses. In addition to the hormone-receptor interfaces, there is also a substantial contact surface between the carboxyl-terminal domains of the receptors. The relative extents of the contact areas support a sequential mechanism for dimerization that may be crucial for signal transduction.
Human growth hormone and extracellular domain of its receptor: crystal structure of the complex.,de Vos AM, Ultsch M, Kossiakoff AA Science. 1992 Jan 17;255(5042):306-12. PMID:1549776
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.