Abstract |
Chicken parathyroid hormone ( cPTH) has been reported to stimulate adrenal steroidogenesis and to have unusual potency on traditional PTH target tissues. To evaluate these properties, chicken PTH-(1-88) has been expressed in Escherichia coli using a plasmid encoding a fusion protein which links together growth hormone, a factor Xa recognition site, and chicken PTH-(1-88). The growth hormone- cPTH fusion protein required the presence of 0.02% sodium dodecyl sulfate to remain in solution and be cleaved by factor Xa. The high performance liquid chromatography-purified recombinant cPTH-(1-88) and chemically synthesized cPTH-(1-34) had similar potency in rat osteosarcoma (ROS 17/2.8) cells, opossum kidney (OK) cells, and dispersed primary chicken kidney cells. The biologic potencies of cPTH-(1-34) and cPTH-(1-88) in radioreceptor binding and cAMP generation in both bone- and kidney-derived cell lines were less than those of human (h)PTH-(1-34). In dispersed chicken kidney cells, cAMP production by cPTH-(1-34) and cPTH-(1-88) was similar to that stimulated by human PTH-(1-34). No stimulation of steroidogenesis could be detected when recombinant chicken PTH-(1-88) was added to dispersed chicken adrenal cells. The biologic activity of recombinant chicken PTH-(1-88) purified from E. coli was comparable with that of chicken PTH-(1-88) expressed by mammalian COS cells. Thus, the full-length chicken PTH did not exhibit enhanced potency, when compared with human PTH in ROS 17/2.8, OK cell lines, and dispersed chicken kidney cells and did not demonstrate the novel steroidogenic action previously reported in adrenal cells. The successful production of chicken PTH-(1-88) will enhance our understanding of the structure-activity relationships for PTH, particularly the sequence-dependent metabolism of the hormone.
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Authors | S K Lim, T Gardella, A Thompson, J Rosenberg, H Keutmann, J Potts Jr, H Kronenberg, S Nussbaum |
Journal | The Journal of biological chemistry
(J Biol Chem)
Vol. 266
Issue 6
Pg. 3709-14
(Feb 25 1991)
ISSN: 0021-9258 [Print] United States |
PMID | 1847386
(Publication Type: Journal Article)
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Chemical References |
- Parathyroid Hormone
- Cyclic AMP
- Factor Xa
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Topics |
- Animals
- Chickens
- Chromatography, High Pressure Liquid
- Cyclic AMP
(metabolism)
- Electrophoresis, Polyacrylamide Gel
- Escherichia coli
(genetics)
- Factor Xa
(pharmacology)
- Gene Expression Regulation, Bacterial
- Genes, Bacterial
- Immunohistochemistry
- Parathyroid Hormone
(biosynthesis, isolation & purification, metabolism)
- Plasmids
- Radioligand Assay
- Rats
- Tumor Cells, Cultured
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