Prothoracicotropic Hormone

TOR signaling is involved in PTTH-stimulated ecdysteroidogenesis by prothoracic glands in the silkworm, Bombyx mori

“…PTTH stimulates general protein synthesis and some specific protein synthesis. It was demonstrated that PTTH-stimulated protein synthesis is required for increased ecdysteroidogenesis, because translation inhibitors, such as cycloheximide and puromycin, block PTTH-stimulated ecdysteroidogenesis (Kulesza et al, 1994;Rybczynski and Gilbert, 1994;Dauphin-Villemant et al, 1995;Smith and Rybczynski, 2012). However, it is not very clear how PTTH regulates protein synthesis of prothoracic glands.…”

“…A neuropeptide, known as the prothoracicotropic hormone (PTTH), produced by brain neurosecretory cells activates ecdysteroidogenesis by prothoracic glands (Rybczynski, 2005;Marchal et al, 2010;Smith and Rybczynski, 2012). PTTH has been suggested to be structurally similar to certain mammalian growth factors (Noguti et al, 1995).…”

Involvement of reactive oxygen species in PTTH-stimulated ecdysteroidogenesis in prothoracic glands of the silkworm, Bombyx mori

“…In insects, a neuropeptide, known as the prothoracicotropic hormone (PTTH) which is produced by brain neurosecretory cells, activates ecdysteroidogenesis in prothoracic glands (PGs), and thus plays a critical role in regulating growth, development, and metamorphosis (Rewitz et al, 2009a;Marchal et al, 2010;Smith and Rybczynski, 2012). The cellular events activated by PTTH in PGs have been extensively studied and results showed that upon binding to the PTTH receptor, PTTH appears to initiate a signaling transduction network (Rewitz et al, 2009a;Marchal et al, 2010;Smith and Rybczynski, 2012).…”

“…The cellular events activated by PTTH in PGs have been extensively studied and results showed that upon binding to the PTTH receptor, PTTH appears to initiate a signaling transduction network (Rewitz et al, 2009a;Marchal et al, 2010;Smith and Rybczynski, 2012). Initial investigations indicated that PTTH-stimulated cAMP and Ca 2þ are intracellular second messengers in both Manduca sexta (Smith et al, 1984(Smith et al, , 1985Fellner et al, 2005) and Bombyx mori (Gu et al, 1996(Gu et al, , 1998Birkenbeil and Dedos, 2002).…”

A molt timer is involved in the metamorphic molt inManduca sextalarvae

“…Callier and Nijhout (14) described that, under poor food conditions, larvae could nevertheless undergo molting using a mechanism that is independent of size, and, indeed, appears to be independent of the brain, the source of the prothoracicotropic hormone (PTTH) that normally drives the ecdysteroid surges needed for molting (15). We examine the effects of challenges in nutrition on allatectomized (CAX) larvae that no longer have JH to impose a size-dependent suppression of metamorphosis.…”