ADAMTS-1: A cellular disintegrin and metalloprotease with thrombospondin motifs is a target for parathyroid hormone in bone.
PTH stimulates bone formation in animals and humans, and the expressions of a number of genes have been implicated in the mediation of this effect. To discover new bone factors that initiate and support this phenomenon we used differential display RT-PCR and screened for genes that are selectively expressed in osteoblast-enriched femoral metaphyseal primary spongiosa of young male rats after a single s.c. injection of human PTH-(1-38) (8 microg/100 g). We show that one of the messenger RNAs that is up-regulated in bone is ADAMTS-1, a new member of the ADAM (A disintegrin and metalloprotease) gene family containing thrombospondin type I motifs. ADAMTS-1 consists of multiple domains common to ADAM family of proteins, including pro-, metalloprotease-like, and disintegrin-like domains. However, unlike other ADAMs, ADAMTS-1 does not possess a transmembrane or cytoplasmic domain and is a secreted protein. Northern blot analysis confirmed that ADAMTS-1 was up-regulated in both metaphyseal (14- to 35-fold) and diaphyseal (4.2-fold) bone 1 h after PTH-(1-38) injection and returned to control levels by 24 h. We also analyzed the regulation of ADAMTS-1 in response to various PTH/PTH-related peptide (PTHrP) analogs and found that PTH-(1-31) and PTHrP-(1-34), which activate the protein kinase A (PKA) pathway, induce ADAMTS-1 expression 1 h after injection, whereas PTH-(3-34) and PTH-(7-34), which do not activate the PKA pathway, did not regulate expression. To investigate the effect of other osteotropic agents, we analyzed ADAMTS-1 expression after a single dose of PGE2 (6 mg/kg) and found that it was up-regulated 1 h after injection and returned to control levels by 6 h. In vitro ADAMTS-1 is expressed in primary osteoblasts and osteoblastic cell lines, but was not detectable in osteoclasts generated from macrophage colony-stimulating factor/receptor activator of NF-kappaB ligand/transforming growth factor-beta1-treated bone marrow cells. Treatment of UMR 106 osteosarcoma cells with PTH, PGE2, forskolin, or (Bu)2cAMP increased ADAMTS-1 expression 7-, 4-, 5-, and 5-fold, respectively. Also, in vitro treatment with 1alpha,25-dihydroxyvitamin D3 increased ADAMTS-1 expression 3-fold. Tissue distribution analysis showed that ADAMTS-1 is expressed at high levels in many tissues, including the heart, lung, liver, skeletal muscle, and kidney. Taken together, these results demonstrate that ADAMTS-1 is specifically up-regulated in bone and osteoblasts by the osteotropic agents PTH, PTHrP, and PGE2 possibly via the cAMP/PKA pathway. We speculate that the rapid and transient increase in ADAMTS-1 expression may contribute to some of the effects of PTH on bone turnover.
Miles
R R
RR
Endocrine Division, Lilly Research Laboratories, Indianapolis, Indiana 46285, USA.
Sluka
J P
JP
Halladay
D L
DL
Santerre
R F
RF
Hale
L V
LV
Bloem
L
L
Thirunavukkarasu
K
K
Galvin
R J
RJ
Hock
J M
JM
Onyia
J E
JE
D051722:ADAM Proteins; D000071097:ADAMTS1 Protein; D000818:Animals; D001842:Bone and Bones / Q000201:enzymology*; D002117:Calcitriol / Q000494:pharmacology; D002417:Cattle; D017868:Cyclic AMP-Dependent Protein Kinases / Q000378:metabolism; D015232:Dinoprostone / Q000494:pharmacology; D019483:Disintegrins / Q000235:genetics* / Q000378:metabolism; D004789:Enzyme Activation / Q000187:drug effects; D005269:Femur; D005786:Gene Expression Regulation / Q000187:drug effects*; D006801:Humans; D007700:Kinetics; D008297:Male; D008666:Metalloendopeptidases / Q000235:genetics* / Q000378:metabolism; D009928:Organ Specificity; D010006:Osteoblasts / Q000201:enzymology; D010010:Osteoclasts / Q000201:enzymology; D012516:Osteosarcoma / Q000201:enzymology; D010281:Parathyroid Hormone / Q000494:pharmacology*; D044162:Parathyroid Hormone-Related Protein; D010446:Peptide Fragments / Q000494:pharmacology; D011506:Proteins / Q000494:pharmacology; D012333:RNA, Messenger / Q000032:analysis; D051381:Rats; D011919:Rats, Inbred Strains; D020133:Reverse Transcriptase Polymerase Chain Reaction; D014407:Tumor Cells, Cultured
D019483:Disintegrins; C470121:PTHLH protein, human; D010281:Parathyroid Hormone; D044162:Parathyroid Hormone-Related Protein; D010446:Peptide Fragments; D011506:Proteins; D012333:RNA, Messenger; C035747:parathyroid hormone (1-38); D017868:Cyclic AMP-Dependent Protein Kinases; D051722:ADAM Proteins; D000071097:ADAMTS1 Protein; C103859:ADAMTS1 protein, human; C486324:Adamts1 protein, rat; D008666:Metalloendopeptidases; D002117:Calcitriol; D015232:Dinoprostone