Meeting Abstract
Hormones play major roles during development and reproduction in multicellular organisms. However, the evolution and development of endocrine glands and hormone biosynthesis are not well understood. The POU factor Ventral veins lacking (Vvl) has recently been shown to play a critical role in endocrine regulation during larval development and endocrine gland development in holometabolous insects. In this study, the role of vvl on reproduction and embryogenesis was examined in the hemimetabolous milkweed bug, Oncopeltus fasciatus. Silencing the expression of vvl using RNA interference (RNAi) in day 1 adult Oncopeltus led to reduced egg production. The potential role of vvl in adult endocrine regulation during oogenesis was explored using hormone treatments. In situ hybridization of vvl expression and one of the ecdysteroid biosynthesis genes, phantom (phm), showed that vvl is expressed in the developing prothoracic glands during embryogenesis. A comparison of phm expression between embryos of normal wild-type and of vvl knockdown females indicates that vvl likely regulates the formation of endocrine glands. Given that in mammals, mutations in the vertebrate homolog of Vvl, POU3F2, can lead to hypogonadism, our study suggests that the role of vvl in endocrine gland formation and reproduction may be an ancient evolutionarily conserved process.
