Primary structure of an analog of crustacean pigment-dispersing hormone from the lubber grasshopper Romalea microptera

• Published in: The Journal of biological chemistry Vol. 262; no. 6; pp. 2672 - 2675
• Main Authors: Rao, K.R., Mohrherr, C.J., Riehm, J.P., Zahnow, C.A., Norton, S., Johnson, L., Tarr, G.E.
• Format: Journal Article
• Language: English
• Published: Bethesda, MD Elsevier Inc 25.02.1987; American Society for Biochemistry and Molecular Biology
• Subjects: Acrididae; Amino Acid Sequence; Aminoacids, peptides. Hormones. Neuropeptides; Analytical, structural and metabolic biochemistry; Animals; Biological and medical sciences; Chromatography, High Pressure Liquid; Fundamental and applied biological sciences. Psychology; Grasshoppers - analysis; Invertebrate Hormones - analysis; Pigmentation; Proteins; Romalea microptera; Primary structure; Invertebrata; Arthropoda; Analog; Insecta; Peptide hormone
• ISSN: 0021-9258; 1083-351X
• DOI: 10.1016/S0021-9258(18)61559-5

An octadecapeptide capable of inducing pigment dispersion in the chromatophores of the fiddler crab Uca pugilator has been isolated from lyophilized heads of the lubber grasshopper Romalea microptera. This pigment-dispersing factor (PDF) was purified by gel filtration, ion-exchange chromatography, partition chromatography, and reversed-phase high performance liquid chromatography. Automated gas-phase sequencing, followed by the identification of the carboxyl-terminal amide, established the primary structure of this PDF as Asn-Ser-Glu-Ile-Ile-Asn-Ser-Leu-Leu-Gly-Leu-Pro-Lys-Leu-Leu-Asn-Asp-Ala- NH2. This structure was confirmed by chemical synthesis and by demonstrating that the synthetic and native PDF displayed identical chromatographic behavior and biological activity. The Romalea PDF is structurally related to the crustacean pigment-dispersing hormones (PDHs), which are also octadecapeptides. The sequence of grasshopper PDF shows 78% homology with beta-PDH (from the crabs U. pugilator and Cancer magister) and 50% homology with alpha-PDH (from the prawn Pandalus borealis). This study provides the first direct chemical evidence for the structural relatedness of insect PDF to the crustacean PDHs, thus identifying them as an authentic family of arthropod peptides.