Characterization and location of post-translational modifications on chromogranin B from bovine adrenal medullary chromaffin granules.
Bovine chromoganin B (CGB)/secretogranin I, an acidic protein with a sequence of 626 residues and an isoelectric point of 5.2 is a major member of the chromogranin/secretogranin (CG/Sg) family. The difference between the theoretical molecular mass (76 kDa) and the value estimated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis results from post-translational modifications (glycosylation, phosphorylation and sulfation) and from the abundance of acidic residues (D 4.6%, and E 16.5%). Although the sequence of CGB is known, the structural analyses of the post-translational modifications have so far not been carried out. In the present study, using a combination of proteomic techniques including two-dimensional gel electrophoresis, Western blot, high-performance liquid chromatography purification, enzymatic digestion, sequencing, carbohydrate analysis, matrix-assisted laser desorption/ionization-time of flight and liquid chromatography mass spectrometry analysis, we have located 18 post-translational modifications on bovine CGB, isolated from adrenal medulla chromaffin granules. Furthermore, we have identified at the molecular level the presence of a mutation M/V on position 577 of natural CGB. All together these data reflect the complex structure of this protein marker of the neuroendocrine system.
Gasnier
Claire
C
INSERM Unité 575, Physiopathologie du Système Nerveux, Strasbourg, France.
Lugardon
Karine
K
Ruh
Olivier
O
Strub
Jean-Marc
JM
Aunis
Dominique
D
Metz-Boutigue
Marie-Hélène
MH
D000313:Adrenal Medulla / Q000737:chemistry*; D000595:Amino Acid Sequence; D024342:Amino Acids, Acidic; D000818:Animals; D002417:Cattle; D002837:Chromaffin Granules / Q000737:chemistry*; D002864:Chromogranins / Q000737:chemistry / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism*; D008969:Molecular Sequence Data; D008970:Molecular Weight; D009154:Mutation; D011499:Protein Processing, Post-Translational; D017434:Protein Structure, Tertiary; D020543:Proteome; D040901:Proteomics / Q000379:methods; D020539:Sequence Analysis, Protein; D017386:Sequence Homology, Amino Acid
D024342:Amino Acids, Acidic; D002864:Chromogranins; D020543:Proteome