Desert locust swarms occasionally cause severe ecological and economic damage, particularly in Countries of northwest Africa. However, the physiological mechanisms underlying locust phase transition, the switch Of the solitarious to the gregarious phase, remain elusive. Therefore, identification of molecular changes linked to this phenomenon represents a primary requirement to start unraveling this enignia. The present paper provides novel information oil phase-related molecular markers For locust phase transition. We present a detailed quantitative real-time RT-PCR analysis of two distinct neuroparsin precursor transcripts (Scg-NPP3 and Scg-NPP4) in the brain and in abdominal tissues of gregarious and solitarious desert locusts (Schistocerca gregaria). Our data reveal different temporal changes of these transcripts in the Cat body during the adult stage of both phases. We. hereby, present novel scientific evidence for a phase-dependent regulation of these particular peptide hormone encoding transcripts and assign them as possible molecular markers in the process of locust phase transition. (c) 2006 Elsevier Inc. All rights reserved.