Y-receptor affinity modulation by the design of pancreatic polypeptide/neuropeptide Y chimera led to Y(5)-receptor ligands with picomolar affinity.
Neuropeptide Y (NPY) and pancreatic polypeptide (PP) bind to the Y-receptors with very different affinities: NPY has high affinity for the receptors Y(1), Y(2) and Y(5), while PP binds only to Y(4)-receptor with picomolar affinity. By exchanging of specific amino acid positions between the two peptides, we developed 38 full-length PP/NPY chimeras with binding properties that are completely different from those of the two native ligands. Pig NPY (pNPY) analogs containing the segment 19-23 from human PP (hPP) bound to the Y-receptors with much lower affinity than NPY itself. The affinity of the hPP analog containing the pNPY segments 1-7 and 19-23 was comparable to that of pNPY at the Y(1)- and Y(5)-receptor subtypes, and to that of hPP at the Y(4)-receptor. Furthermore, the presence of the segments 1-7 from chicken PP (cPP) and 19-23 from pNPY within the hPP sequence led to a ligand with IC(50) of 40 pM at the Y(5)-receptor. This is the most potent Y(5)-receptor ligand known so far, with 15-fold higher affinity than NPY.
Cabrele
C
C
Department of Applied Bioscience, ETH Zurich, Winterthurerstrasse 190, 8057, Zurich, Switzerland.
Wieland
H A
HA
Langer
M
M
Stidsen
C E
CE
Beck-Sickinger
A G
AG
D000595:Amino Acid Sequence; D000818:Animals; D001667:Binding, Competitive; D002460:Cell Line; D002645:Chickens; D002942:Circular Dichroism; D006224:Cricetinae; D006801:Humans; D020128:Inhibitory Concentration 50; D007700:Kinetics; D008024:Ligands; D010191:Pancreatic Polypeptide / Q000737:chemistry* / Q000378:metabolism*; D010452:Peptide Biosynthesis; D011485:Protein Binding; D051381:Rats; D017476:Receptors, Neuropeptide Y / Q000737:chemistry* / Q000378:metabolism*; D011993:Recombinant Fusion Proteins / Q000737:chemistry; D017386:Sequence Homology, Amino Acid; D013329:Structure-Activity Relationship; D013552:Swine
D008024:Ligands; D017476:Receptors, Neuropeptide Y; D011993:Recombinant Fusion Proteins; D010191:Pancreatic Polypeptide