Mass spectrometric evidence for the deficiency in the dark-color-inducing hormone, [His(7)]-corazonin in an albino strain of Locusta migratoria as well as for its presence in solitary Schistocerca gregaria

A factor present in the brain and corpus cardiacum responsible for the indu ction of dark colour in Locusta migratoria was recently isolated and identi fied from the corpora cardiaca of normally pigmented locusts. The purificat ion of this factor, designated as [His(7)]-corazonin was monitored using an albino mutant from a laboratory colony of an Okinawa (Japan) strain. In th is study, we provide unequivocal mass spectrometric evidence that the brain and the corpora cardiaca of this albino Locusta mutant are deficient in [H is(7)]-corazonin. Previously, [His(7)]-corazonin was shown to be responsibl e for the induction of dark body colour patterns as observed in crowded loc usts. Using nanoflow-liquid chromatography-mass spectrometry, we demonstrat ed that this dark colour-inducing hormone is, however, present in the corpo ra cardiaca of solitary locusts (Schistocerca gregaria). (C) 2001 Wiley-Lis s, Inc.