The growth hormone (GH) receptor (GHR) is a mammalian plasma membrane protein whose internalization is mediated by the ubiquitin-proteasome pathway. GH internalization and degradation are inhibited when cells are treated with proteasome inhibitors. Here we show that a GHR truncated at residue 369 can enter the cells in the presence of a proteasome inhibitor, but that the subsequent lysosomal degradation of GH is blocked. Lysosomal inhibitors prolong the half-life of both receptor and ligand. Experiments with antibodies against different receptor tail sections show that degradation of the GHR cytosolic domain precedes degradation of the extracellular GH-binding domain. A possible role for the ubiquitin-proteasome pathway in the degradation of the receptor and ligand is discussed.
The ubiquitin-proteasome pathway regulates lysosomal degradation of the growth hormone receptor and its ligand
P. van Kerkhof, G. J. Strous; The ubiquitin-proteasome pathway regulates lysosomal degradation of the growth hormone receptor and its ligand. Biochem Soc Trans 1 August 2001; 29 (4): 488–493. doi: https://doi.org/10.1042/bst0290488
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