Characterization of crustacean hyperglycemic hormone from the crayfish (Procambarus clarkii): multiplicity of molecular forms by stereoinversion and diverse functions.
The complete amino acid sequence of two forms of crustacean hyperglycemic hormone (CHH) from the X-organ sinus gland complex of crayfish (Procambarus clarkii) has been determined. There are two variants of P. clarkii CHH (Prc-CHH), I and II, which can be separated by reversed-phase high-performance liquid chromatography (RP-HPLC). Each variant was oxidized by performic acid and then cleaved with lysyl endopeptidase. Intact hormone was also digested with trypsin and endoproteinase Asp-N, successively. The resulting fragments were separated by RP-HPLC and subjected to sequence analyses by a gas-phase sequencer and tandem mass spectrometry. Both variants contain 72 amino acid residues with three disulfide linkages, at positions 7-43, 23-39, and 26-52, and differ from each other by the D/L epimerization of phenylalanine at position 3; Prc-CHH-II contains D-amino acid. Injections of Prc-CHH-I and Prc-CHH-II at a dose of 12.5 pmol resulted in significant increase of hemolymph glucose levels in the crayfish. The hormones are also active in repressing ecdysteroid synthesis at concentrations of 250 mM (Prc-CHH-I) and 25 nM (Prc-CHH-II) in Y-organ culture. These results may indicate that the stereoinversion in the CHH molecule leads to an important alternation in hormonal functions during crustacean development.
Yasuda
A
A
Suntory Institute for Bioorganic Research, Osaka, Japan.
Yasuda
Y
Y
Fujita
T
T
Naya
Y
Y
D000595:Amino Acid Sequence; D000596:Amino Acids / Q000032:analysis; D000818:Animals; D060829:Arthropod Proteins; D003400:Astacoidea / Q000378:metabolism*; D002851:Chromatography, High Pressure Liquid; D005260:Female; D007447:Invertebrate Hormones / Q000737:chemistry / Q000378:metabolism / Q000502:physiology; D008969:Molecular Sequence Data; D008970:Molecular Weight; D009419:Nerve Tissue Proteins / Q000737:chemistry* / Q000378:metabolism / Q000502:physiology*; D013329:Structure-Activity Relationship
D000596:Amino Acids; D060829:Arthropod Proteins; D007447:Invertebrate Hormones; D009419:Nerve Tissue Proteins; C015947:hyperglycemic hormone, crustacean