Nuclear receptor Metamorphosis

the bet (2 ly s th f th n a BgHR4 is an essential gene required for successfully completing nymphal–nymphal and nymphal–adult h andm phal s asts w te pupa s. In h opmen Although there is a detailed understanding of the molecular mechanisms by which 20E regulates the metamorphic process in holometabolous insects, especially in Drosophila melanogaster (Thummel, 1996; Riddiford et al., 2000, 2003; King-Jones and Thummel, 2005), little is known about how this hormone operates during the development of hemimetabolous species. Given that of nuclear receptors, which is present in most tissues of B. germanica, not only controls ecdysteroid biosynthesis and molt-ing during each nymphal instar but also metamorphic-associated processes, such as cell proliferation in wings and in follicular epi-thelium, and the programmed cell death of the prothoracic glan