TY - JOUR
T1 - Salmon growth hormone receptor
T2 - Molecular cloning, ligand specificity, and response to fasting
AU - Fukada, Haruhisa
AU - Ozaki, Yuichi
AU - Pierce, Andrew L.
AU - Adachi, Shinji
AU - Yamauchi, Kohei
AU - Hara, Akihiko
AU - Swanson, Penny
AU - Dickhoff, Walton W.
N1 - Funding Information:
This research was supported by JSPS postdoctoral fellowship for research abroad to H.F. and an NRI-CSREES-USDA Grant (Award No. 2003-35206-13631). We gratefully thank Dr. Saneyoshi for the gift of the masu salmon liver cDNA library and recombinant chum salmon GH, and Mr. J.T. Dickey for assistance with this research. We also thank Ms. K. Cooper for measuring plasma IGF-I level.
PY - 2004/10
Y1 - 2004/10
N2 - To better understand the role of growth hormone in regulating fish growth, the cDNA of growth hormone receptor (GHR) was cloned from the liver of masu salmon (Oncorhynchus masou) and characterized. The masu salmon GHR (msGHR) sequence revealed common features of a GHR, including a (Y/F)GEFS motif in the extracellular domain, a single transmembrane region, and Box 1 and Box 2 in the intracellular domain. However, the amino acid sequence identity was low (≤49%) compared to GHRs of other vertebrates including seven teleosts, and the putative msGHR protein lacked one pair of cysteine residues in the extracellular domain. To verify the identity of the msGHR, the recombinant protein of the extracellular domain was expressed with a histidine tag protein (His-msGHR-ECD), refolded and purified for analysis of its ligand specificity. In competition experiments, the specific binding between His-msGHR-ECD and radioiodine-labeled salmon GH was displaced completely by only salmon GH, and not by salmon prolactin or somatolactin. A real-time RT-PCR assay was used to measure salmon GHR mRNA in the liver of fed and fasted coho salmon (Oncorhynchus kisutch). The levels of hepatic GHR mRNA were lower in fasted fish compared to fed fish after 3 weeks, suggesting that GHR gene expression is reduced following a long-term fast. These results confirm the identity of the salmon GHR based on ligand specificity and response to fasting.
AB - To better understand the role of growth hormone in regulating fish growth, the cDNA of growth hormone receptor (GHR) was cloned from the liver of masu salmon (Oncorhynchus masou) and characterized. The masu salmon GHR (msGHR) sequence revealed common features of a GHR, including a (Y/F)GEFS motif in the extracellular domain, a single transmembrane region, and Box 1 and Box 2 in the intracellular domain. However, the amino acid sequence identity was low (≤49%) compared to GHRs of other vertebrates including seven teleosts, and the putative msGHR protein lacked one pair of cysteine residues in the extracellular domain. To verify the identity of the msGHR, the recombinant protein of the extracellular domain was expressed with a histidine tag protein (His-msGHR-ECD), refolded and purified for analysis of its ligand specificity. In competition experiments, the specific binding between His-msGHR-ECD and radioiodine-labeled salmon GH was displaced completely by only salmon GH, and not by salmon prolactin or somatolactin. A real-time RT-PCR assay was used to measure salmon GHR mRNA in the liver of fed and fasted coho salmon (Oncorhynchus kisutch). The levels of hepatic GHR mRNA were lower in fasted fish compared to fed fish after 3 weeks, suggesting that GHR gene expression is reduced following a long-term fast. These results confirm the identity of the salmon GHR based on ligand specificity and response to fasting.
KW - Binding assay
KW - Cloning
KW - Growth hormone
KW - Growth hormone receptor
KW - Insulin-like growth factor-I
KW - Salmon
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U2 - 10.1016/j.ygcen.2004.07.001
DO - 10.1016/j.ygcen.2004.07.001
M3 - Article
C2 - 15474537
AN - SCOPUS:5144232636
SN - 0016-6480
VL - 139
SP - 61
EP - 71
JO - General and Comparative Endocrinology
JF - General and Comparative Endocrinology
IS - 1
ER -