It appears from grafting experiments that the androgenic hormone (AH) of terrestrial isopods has a narrow species-specificity [J. Crust. Biol. 19 (1999) 684], even if AH of different species shared common epitopes [Gen. Comp. Endocrinol. 125 (2002) 218]. To date only the glycosylated AH of the woodlouse Armadillidium vulgare has been deciphered by us [Ann. New York Acad. Sci. 839 (1998) 111; Eur. J. Biochem. 262 (1999) 727] and [Biochem. Biophys. Res. Commun. 264 (1999) 419] have confirmed the primary structure of this protein. We reported in the present paper the characterization of the AH in another species Porcellio scaber by a combination of microsequencing, mass spectrometry, and molecular cloning. We found only one glycoform which consisted of two peptide chains, A and B, of 31 and 44 amino acids, respectively, with A chain carrying on Asn 18 a N-glycosylated moiety, size of which has been determined by MALDI-MS measurements. The expected structure of the glycosylation was proposed. The deduced amino acid sequence of the AH precursor was mainly identical to the one obtained independently by another group [Zool. Sci. 20 (2003) 75]. We also showed that AH gene is exclusively expressed in androgenic glands. Sequence comparison with A. vulgare and P. scaber (population of Japan) AH was discussed.
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