Production of parathyroid hormone-related protein by a rat parathyroid cell line.
Parathyroid hormone-related protein (PTHrP), the peptide associated with humoral hypercalcemia of malignancy, has been identified in fetal and adult parathyroid glands. We here report a sub-clone of a rat parathyroid cell line which secretes a single peptide species corresponding in size to PTHrP(1-84). Biological activity of the secretion product was blocked by a specific antiserum against PTHrP, but not by parathyroid hormone (PTH) antiserum. Secretion of PTHrP by these cells was regulated by extracellular calcium in the physiological range. A single messenger RNA species for PTHrP was identified, though PTH mRNA could not be shown in these cells. Hybrid CAT genes containing 700-1000 bp of 5'-flanking DNA from the human PTH or PTHrP genes were transfected into these cells, and the PTHrP gene was expressed at 10-fold higher levels than the PTH gene. These cells thus provide a valuable model system for investigation expression of PTHrP in a non-transformed cell line.
Zajac
J D
JD
Department of Medicine, Royal Melbourne Hospital, University of Melbourne, Victoria, Australia.
Callaghan
J
J
Eldridge
C
C
Diefenbach-Jagger
H
H
Suva
L J
LJ
Hudson
P
P
Moseley
J M
JM
Michelangeli
V P
VP
Pasquini
G
G
D000262:Adenylyl Cyclases / Q000378:metabolism; D000818:Animals; D002118:Calcium / Q000494:pharmacology; D002460:Cell Line; D005786:Gene Expression Regulation; D009363:Neoplasm Proteins / Q000096:biosynthesis* / Q000235:genetics / Q000378:metabolism; D010280:Parathyroid Glands / Q000166:cytology / Q000378:metabolism*; D010281:Parathyroid Hormone / Q000096:biosynthesis; D044162:Parathyroid Hormone-Related Protein; D012333:RNA, Messenger / Q000032:analysis; D051381:Rats; D011994:Recombinant Proteins / Q000096:biosynthesis; D014162:Transfection
D009363:Neoplasm Proteins; D010281:Parathyroid Hormone; D044162:Parathyroid Hormone-Related Protein; D012333:RNA, Messenger; D011994:Recombinant Proteins; D000262:Adenylyl Cyclases; D002118:Calcium