Sequences of elongation factors-1α and -1γ and stimulation by juvenile hormone in Locusta migratoria

Two cDNAs encoding the alpha and gamma subunits of translation elongation factor-1 (EF-1) have been cloned and sequenced from the African migratory locust, Locusta migratoria. Southern blotting and real-time PCR analyses indicated that these sequences represent single copy genes. Comparison with sequences from other species indicated greater conservation for EF-1alpha than for EF-1gamma. The developmental profiles for EF-1alpha and -1gamma mRNA expression in the fat body paralleled reported changes in the hemolymph juvenile hormone (JH) titer in the fifth instar and were elevated during early reproductive maturation in the female adult. In maturing adults, there was a greater accumulation of EF-1alpha and -1gamma transcripts in females than in males. The levels of both transcripts were greatly increased by an enriched diet, previously shown to elevate JH titers and accelerate vitellogenin production. Treating JH-deprived adult females with the JH analog, methoprene, resulted in more than doubling of transcript levels of both genes, supporting the hypothesis that JH could stimulate the accumulation of LmEF-1alpha and -1gamma transcripts. We suggest that production of elongation factors, increased by JH, may contribute to the massive protein synthesis required for egg production. (C) 2002 Elsevier Science Ltd. All rights reserved.