Ser(13)-phosphorylated PYY from porcine intestine with a potent biological activity.
We have isolated a posttranslationally modified form of peptide YY (PYY) from porcine intestine and shown by MALDI-TOF and electrospray tandem mass spectrometry that it is phosphorylated at Ser(13). Phospho-PYY exhibits high affinity for binding to neuropeptide Y (NPY) receptors Y1, Y2 and Y5. The IC(50) values with the Y1, Y2, and Y5 receptor subtypes were for NPY 2.4, 3.1, and 3.3 nM, for PYY 2.3, 0.94, and 3.2 nM, and for phospho-PYY 4.6, 2.2, and 5.5 nM, respectively. Phospho-PYY potently inhibits forskolin-stimulated cAMP accumulation in SK-N-MC cells with an IC(50) value of 0.5 nM compared to 0.15 nM for non-phosphorylated PYY. The finding of phosphorylation of PYY is unusual among hormonal peptides, and emphasizes the importance of direct protein analysis of gene products.
Chen
Z
Z
Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Stockholm, Sweden.
Eriste
E
E
Jonsson
A P
AP
Norberg
A
A
Nepomuceno
D
D
Lovenberg
T W
TW
Bergman
T
T
Efendic
S
S
Jörnvall
H
H
Sillard
R
R
D000595:Amino Acid Sequence; D000818:Animals; D000242:Cyclic AMP / Q000378:metabolism; D006801:Humans; D007413:Intestinal Mucosa / Q000378:metabolism*; D019894:Peptide YY / Q000737:chemistry / Q000378:metabolism*; D010766:Phosphorylation; D020539:Sequence Analysis, Protein; D017386:Sequence Homology, Amino Acid; D012694:Serine / Q000378:metabolism*; D013552:Swine; D014407:Tumor Cells, Cultured
D019894:Peptide YY; D012694:Serine; D000242:Cyclic AMP