Regulation of Schistocerca gregaria neuroparsin transcript levels by juvenile hormone and 20-hydroxyecdysone.
Neuroparsins (NPs) are small proteins that were originally discovered in the pars intercerebralis-corpus cardiacum neurosecretory complex of the migratory locust brain. From the desert locust, Schistocerca gregaria, we recently cloned four different transcripts, each coding for a distinct NP-related peptide. In addition to the brain, some NP-like precursor (Scg-NPP) transcripts also occur in a number of peripheral tissues, and their expression levels are controlled in a gender- and stage-dependent manner. Previous studies revealed a close correlation between Scg-NPP transcript levels and the gonotrophic cycle. In the present report, we demonstrate that certain Scg-NPP transcript levels are significantly altered upon injection of juvenile hormone (JH) or 20-hydroxyecdysone (20E) in adult gregarious desert locusts (five days after final ecdysis). While Scg-NPP1 transcript levels did not significantly change as a result of hormone treatment (animals were analyzed 24 h after injection), Scg-NPP2, Scg-NPP3, and Scg-NPP4 displayed hormone-dependent regulation in various tissues. Scg-NPP2 and Scg-NPP3 transcript levels significantly increased in the brain of JH-treated locusts. In addition, JH induction of Scg-NPP3 and Scg-NPP4 transcripts was observed in male fat body and in male and female gonads. Furthermore, 20E injection also induced Scg-NPP2, Scg-NPP3, and Scg-NPP4 transcripts in desert locust gonads. This is the first report showing NP-like precursor gene expression in insect ovaries. Our study indicates that the expression levels of some Scg-NPP transcripts are regulated by developmental hormones, suggesting a close correlation between NP expression and the endocrine control of the reproductive cycle.
Claeys
Ilse
I
Laboratory of Developmental Physiology, Genomics and Proteomics, K.U. Leuven, Leuven, Belgium. Ilse.Claeys@bio.kuleuven.be
Breugelmans
Bert
B
Simonet
Gert
G
Franssens
Vanessa
V
Van Soest
Sofie
S
Broeck
Jozef Vanden
JV
D000199:Actins / Q000096:biosynthesis; D000818:Animals; D017931:DNA Primers / Q000737:chemistry; D004441:Ecdysterone / Q000494:pharmacology*; D005260:Female; D015870:Gene Expression / Q000187:drug effects*; D020869:Gene Expression Profiling / Q000379:methods; D006110:Grasshoppers / Q000502:physiology*; D007267:Injections; D007301:Insect Hormones / Q000096:biosynthesis / Q000235:genetics / Q000502:physiology*; D007605:Juvenile Hormones / Q000494:pharmacology*; D008297:Male; D020133:Reverse Transcriptase Polymerase Chain Reaction / Q000379:methods
D000199:Actins; D017931:DNA Primers; D007301:Insect Hormones; D007605:Juvenile Hormones; D004441:Ecdysterone