Identification of variant forms of the neuroendocrine peptide galanin.
Galanin is a neuroendocrine peptide widely distributed in the central and peripheral nervous systems and in endocrine tissues. Using radioimmunoassays, chromatographic separations, and tandem mass spectrometry, we have identified a series of five variant forms of galanin purified from porcine upper intestine. The modified variants include three beta-aspartyl-shifted forms, an oxidized form containing Trp monooxide, and an N-terminally truncated form. All were found to be C-terminally amidated. At least the beta-aspartyl-shifted forms could be of native occurrence. Mechanistic explanations of the mass spectrometric fragmentation patterns of the different forms are suggested.
Norberg
Ake
A
Department of Medical Biochemistry and Biophysics, Karolinska Institutet, SE-171 77 Stockholm, Sweden.
Griffiths
William J
WJ
Hjelmqvist
Lars
L
Jörnvall
Hans
H
Rökaeus
Ake
A
D000595:Amino Acid Sequence; D000818:Animals; D002851:Chromatography, High Pressure Liquid; D019004:Galanin / Q000737:chemistry* / Q000145:classification; D007421:Intestine, Small / Q000737:chemistry; D008969:Molecular Sequence Data; D011863:Radioimmunoassay; D021241:Spectrometry, Mass, Electrospray Ionization / Q000379:methods*; D013552:Swine
D019004:Galanin