Cross-linking of neuropeptide Y to its receptor on rat brain membranes.
The receptor for neuropeptide Y (NPY) was identified on rat brain membranes after covalent labeling with 125I-NPY using the homobifunctional cross-linkers disuccinimido suberate and disuccinimido dithiobis(propionate) and the heterobifunctional photoactive cross-linker succinimido 4-azidobenzoate. Analysis by sodium dodecyl sulfate-polyacrylamide gel electrophoresis followed by autoradiography revealed the presence of two bands at Mr 62,000 and 39,000. Both species showed the same high affinity for 125I-NPY. Exposure to reducing agents did not change the migration of these bands. When the NPY receptor complex was solubilized from the membranes with 1% Triton X-100 and analyzed by gel filtration chromatography, it eluted from a Fractogel TSK 55F column as a peak at approximately 65 kDa. This peak was asymmetric with a shoulder of radioactivity that probably reflects the smaller receptor species. These data indicate that the NPY receptor on rat brain membranes is a monomeric 58-kDa unit (62 kDa minus the mass of the cross-linked NPY) without covalently or noncovalently linked subunits. The smaller 39-kDa species may be an immature form of the 62-kDa species, a second distinct receptor, or a degradation product of the 62-kDa band.
Mannon
P J
PJ
Department of Medicine, Duke University Medical Center, Durham, North Carolina 27710.
Taylor
I L
IL
Kaiser
L M
LM
Nguyen
T D
TD
D000818:Animals; D001921:Brain / Q000378:metabolism*; D003432:Cross-Linking Reagents / Q000494:pharmacology*; D007700:Kinetics; D008297:Male; D008566:Membranes / Q000378:metabolism; D008970:Molecular Weight; D009478:Neuropeptide Y / Q000378:metabolism*; D051381:Rats; D011919:Rats, Inbred Strains; D017476:Receptors, Neuropeptide Y; D017981:Receptors, Neurotransmitter / Q000187:drug effects / Q000378:metabolism*
D003432:Cross-Linking Reagents; D009478:Neuropeptide Y; D017476:Receptors, Neuropeptide Y; D017981:Receptors, Neurotransmitter