• Purity

  >90%, by SDS-PAGE under reducing conditions and visualized by silver stain

• Endotoxin Level

  <0.10 EU per 1 μg of the protein by the LAL method.  

• Activity

  Measured by its ability to inhibit GH-induced proliferation of Nb2?11 rat lymphoma cells. Gout, P.W.     et al. (1980) Cancer Res.     40:2433. The ED    ₅₀ for this effect is 0.7-2.5 ng/mL in the presence of 0.2 ng/mL of rhGH.

• Source

  Mouse myeloma cell line, NS0-derived

  Rat GHR (Phe19 - Arg265) Accession # P16310	RIEGRMD	Human IgG1 (Pro100 - Lys330)
  N-terminus		C-terminus

• Accession #

• N-terminal Sequence    
  Analysis

  Phe19

• Structure / Form

  Disulfide-linked homodimer

• Predicted Molecular Mass

  55.1 kDa (monomer)

• SDS-PAGE

  65-80 kDa, reducing conditions

Background: Growth Hormone R/GHR

Growth hormone (GH), also known as somatotropin, is a member of a family of growth factors that includes prolactin, placental lactogens, proliferins and somatolactin (1, 2). It is synthesized primarily by somatotropes in the anterior pituitary and is released as an endocrine hormone. Other cells and tissues, including lymphoid tissues, can also produce GH (3). GH is a pleiotropic molecule which can act directly or indirectly via IGF-I, to regulate growth and metabolism as well as enhance T cell survival and thymic functions (1, 2, 4). GH exerts its biological actions by binding to the GH receptor (GHR) that is present in many cell types (1, 2). Rat GHR cDNA encodes a 638 amino acid (aa) residue type I transmembrane protein with a 18 aa signal peptide, a 247 aa extracellular domain, a 24 aa transmembrane domain and a 349 aa cytoplasmic domain. An alternatively spliced 297 aa isoform of rat GHR also exists. This 279 aa variant corresponds to the serum GH-binding protein and is identical in sequence to the extracellular domain of the transmembrane protein up to Glu262 (5). Ligation of GHR by GH has been shown to result in receptor dimerization and activation of the JAK/STAT signaling cascade (6). The soluble GHBP has been shown to interfere with GH signaling by competing with the transmembrane receptor of GH. Alternatively, the GHBP has also been shown to enhance GH action by slowing GH clearance (5, 7).

• References:

1. Goffin, V. et al. (1996) Endocrine Rev. 17:385.

2. Le Roith, D. et al. (2001) Endocrine Rev. 22:53.

3. Clark, R. (1997) Endocr. Rev. 18:157.

4. Welniak, L.A. et al. (2002) J. Leukoc. Biol. 71:381.

5. Postel-Vinay, M.C. and J. Finidori (1995) Eur. J. Endocrinol. 133:654.

6. Carter-Su, C. et al. (1996) Annu. Rev. Physiol. 58:187.

7. Frick, G.P. et al. (1998) Endocrinology 139:2824.

• Long Name:

  Growth Hormone Receptor

• Entrez Gene IDs:

  2690 (Human); 14600 (Mouse); 25235 (Rat)

• Alternate Names:

  GH receptor; GHBP; GHR; growth hormone binding protein; Growth Hormone R; growth hormone receptor; serum binding protein; Somatotropin receptor