TY - JOUR
T1 - The expression and function of the OGF-OGFr axis - A tonically active negative regulator of growth - In COS cells
AU - Zagon, Ian S.
AU - Verderame, Michael F.
AU - McLaughlin, Patricia J.
N1 - Funding Information:
This research was supported in part by a grant from the External Research Division of Philip Morris, and a grant with the Pennsylvania Department of Health. The Department specifically disclaims responsibility for any analyses, interpretations or conclusions.
Copyright:
Copyright 2017 Elsevier B.V., All rights reserved.
PY - 2003/10
Y1 - 2003/10
N2 - This study was designed to examine the presence and role of the opioid growth factor (OGF, [Met5]-enkephalin) and the OGF receptor (OGFr) in COS-7 cells; these cells lack classical opioid receptors. Preproenkephalin mRNA, which encodes OGF, was detected by Northern blot analysis, and OGFr mRNA was recorded by RT-PCR. Receptor binding analysis showed specific and saturable binding (Kd = 3.5 nm, Bmax = 44 fmol/mg protein) for OGFr in the nuclear fraction. Both OGF and OGFr were recorded in COS-7 cells by immunocytochemistry. Addition of OGF to log-phase COS-7 cultures depressed growth by 41.6% from control levels, whereas opioid-receptor blockade by the opioid antagonist, naltrexone, increased the number of cells by 29.8% from control values. The effect of OGF was receptor mediated. Exposure to a wide variety of synthetic and natural opioid peptides, including those selective for μ, δ, and κ opioid receptors, showed that only OGF had an effect. Treatment with antisense OGFr oligonucleotides increased the number of cells by over 2-fold compared to wild-type cultures of COS-7 cells and preparations receiving scrambled oligonucleotides. These results indicate that the OGF-OGFr axis is present and functions in COS-7 cells, and in the absence of classical opioid receptors.
AB - This study was designed to examine the presence and role of the opioid growth factor (OGF, [Met5]-enkephalin) and the OGF receptor (OGFr) in COS-7 cells; these cells lack classical opioid receptors. Preproenkephalin mRNA, which encodes OGF, was detected by Northern blot analysis, and OGFr mRNA was recorded by RT-PCR. Receptor binding analysis showed specific and saturable binding (Kd = 3.5 nm, Bmax = 44 fmol/mg protein) for OGFr in the nuclear fraction. Both OGF and OGFr were recorded in COS-7 cells by immunocytochemistry. Addition of OGF to log-phase COS-7 cultures depressed growth by 41.6% from control levels, whereas opioid-receptor blockade by the opioid antagonist, naltrexone, increased the number of cells by 29.8% from control values. The effect of OGF was receptor mediated. Exposure to a wide variety of synthetic and natural opioid peptides, including those selective for μ, δ, and κ opioid receptors, showed that only OGF had an effect. Treatment with antisense OGFr oligonucleotides increased the number of cells by over 2-fold compared to wild-type cultures of COS-7 cells and preparations receiving scrambled oligonucleotides. These results indicate that the OGF-OGFr axis is present and functions in COS-7 cells, and in the absence of classical opioid receptors.
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U2 - 10.1016/j.npep.2003.07.001
DO - 10.1016/j.npep.2003.07.001
M3 - Article
C2 - 14607106
AN - SCOPUS:0345304353
VL - 37
SP - 290
EP - 297
JO - Neuropeptides
JF - Neuropeptides
SN - 0143-4179
IS - 5
ER -