Isolation and structure of two novel 6-kDa dimeric peptides from the corpora cardiaca of the insect Locusta migratoria. Molecular mass determination by mass spectrometry.
We have isolated two major 6-kDa peptides from extracts of corpora cardiaca of adult females of Locusta migratoria. These peptides have been characterized by peptide sequencing and liquid secondary-ion mass spectrometry. They are structurally related dimers, one (6278.5 Da) being a homodimer (A-A chains), the other (6280.5 Da) being a heterodimer (A-B chains). A 60% similarity exists between the A and B chains. Both peptides have been chemically synthesized and the synthetic compounds appeared to be identical to the native ones. Polyclonal antibodies raised against each of these peptides demonstrated that they were contained within the secretory granules of the intrinsic cells of the glandular lobes of the corpora cardiaca. The physiological significance of these two peptides is unknown but, using the synthetic peptides, we are currently probing their biological role.
Hietter
H
H
Laboratoire de chimie organique des substances naturelles, associé au Centre national de la recherche scientifique, Strasbourg, France.
Luu
B
B
Goltzene
F
F
Zachary
D
D
Hoffmann
J
J
Van Dorsselaer
A
A
D000595:Amino Acid Sequence; D000596:Amino Acids / Q000302:isolation & purification; D000818:Animals; D002851:Chromatography, High Pressure Liquid; D003594:Cytoplasmic Granules / Q000032:analysis*; D005088:Exocrine Glands / Q000032:analysis*; D006110:Grasshoppers / Q000032:analysis*; D013058:Mass Spectrometry / Q000379:methods; D015394:Molecular Structure; D008970:Molecular Weight; D010084:Oxidation-Reduction; D010455:Peptides / Q000302:isolation & purification*
D000596:Amino Acids; D010455:Peptides