Characterization of natural vasostatin-containing peptides in rat heart.
Chromogranin A (CGA) is a protein that is stored and released together with neurotransmitters and hormones in the nervous, endocrine and diffuse neuroendocrine systems. As human vasostatins I and II [CGA(1-76) and CGA(1-113), respectively] have been reported to affect vessel motility and exert concentration-dependent cardiosuppressive effects on isolated whole heart preparations of eel, frog and rat (i.e. negative inotropism and antiadrenergic activity), we investigated the presence of vasostatin-containing peptides in rat heart. Rat heart extracts were purified by RP-HPLC, and the resulting fractions analyzed for the presence of CGA N-terminal fragments using dot-blot analysis. CGA-immunoreactive fractions were submitted to western blot and MS analysis using the TOF/TOF technique. Four endogenous N-terminal CGA-derived peptides [CGA(4-113), CGA(1-124), CGA(1-135) and CGA(1-199)] containing the vasostatin sequence were characterized. The following post-translational modifications of these fragments were identified: phosphorylation at Ser96, O-glycosylation (trisaccharide, NAcGal-Gal-NeuAc) at Thr126, and oxidation at three methionine residues. This first identification of CGA-derived peptides containing the vasostatin motif in rat heart supports their role in cardiac physiology by an autocrine/paracrine mechanism.
Glattard
Elise
E
Inserm U575, Physiopathologie du Système Nerveux, Strasbourg, France.
Angelone
Tommaso
T
Strub
Jean-Marc
JM
Corti
Angelo
A
Aunis
Dominique
D
Tota
Bruno
B
Metz-Boutigue
Marie-Hélène
MH
Goumon
Yannick
Y
D000311:Adrenal Glands / Q000737:chemistry; D000595:Amino Acid Sequence; D000818:Animals; D037282:Calreticulin / Q000737:chemistry* / Q000235:genetics / Q000302:isolation & purification; D002417:Cattle; D002851:Chromatography, High Pressure Liquid; D053379:Chromogranin A; D002864:Chromogranins / Q000737:chemistry* / Q000235:genetics / Q000302:isolation & purification; D017124:Conserved Sequence; D006801:Humans; D008297:Male; D013058:Mass Spectrometry; D008969:Molecular Sequence Data; D008970:Molecular Weight; D009206:Myocardium / Q000737:chemistry*; D010446:Peptide Fragments / Q000737:chemistry* / Q000235:genetics / Q000302:isolation & purification; D011499:Protein Processing, Post-Translational; D017434:Protein Structure, Tertiary; D051381:Rats; D017208:Rats, Wistar; D017386:Sequence Homology, Amino Acid; D013045:Species Specificity
D037282:Calreticulin; D053379:Chromogranin A; D002864:Chromogranins; D010446:Peptide Fragments; C121986:vasostatin