Non-canonical Eclosion Hormone-Expressing Cells Regulate Drosophila Ecdysis

Abstract

Eclosion hormone (EH) was originally identified as a brain-derived hormone capable of inducing the behavioral sequences required for molting across insect species. However, its role in this process (called ecdysis) has since been confounded by discrepancies in the effects of genetic and cellular manipulations of EH function in Drosophila. Although knock-out of the Eh gene results in severe ecdysis-associated deficits accompanied by nearly complete larval lethality, ablation of the only neurons known to express EH (i.e. V m neurons) is only partially lethal and surviving adults emerge, albeit abnormally. Using new tools for sensitively detecting Eh gene expression, we show that EH is more widely expressed than previously thought, both within the nervous system and in somatic tissues, including trachea. Ablating all Eh-expressing cells has effects that closely match those of Eh gene knock-out; developmentally suppressing them severely disrupts eclosion. Our results thus clarify and extend the scope of EH action.

Ecdysis‐related neuropeptide expression and metamorphosis in a non‐ecdysozoan bilaterian

“…Accordingly, arthropod ERNs are not only expressed by neurons and neurosecretory cells of the central and peripheral nervous system, but also by non‐neural tissue types, including the midgut, the tracheal system, and specific endocrine glands (Davis 2003; Žitňan and Daubnerová 2016; Scott et al. 2020). In contrast, A. fascicularis ERNs were only detected in bilateral symmetrically arranged pairs of cells, which we consider to be neurons based on their distribution and cell morphology (Fig.…”

Identification and characterization of expression profiles of neuropeptides and their GPCRs in the swimming crab, Portunus trituberculatus

“…EH was originally identified as a brain-derived hormone that is synthesized in ventromedial disposition in the brains of most insects ( Horodyski, Riddiford & Truman, 1989 ). This peptide might play a role in regulation of ecdysis, a common physiological process in insects ( Scott et al., 2020 ). Identification of EH precursors in other members of the Portunidae, such as S. paramamosain ( Bao et al., 2015 ) and S. olivacea ( Christie, 2016b ), implies that these signaling systems are likely to be present in P. trituberculatus .…”

Metabolic Changes in Larvae of Predator Chrysopa sinica Fed on Azadirachtin-Treated Plutella xylostella Larvae

“…A distinct biochemical characteristic of insects is their higher levels of free amino acids in the hemolymph [48], and the likely utilization of the free amino acids as silk protein synthesis to produce cocoon [49]. Furthermore, the eclosion is controlled by three peptide hormones: eclosion hormone, ecdysis-triggering hormone, and crustacean cardioactive peptide [50,51]. The reduction of free amino acids could hamper both pupation and eclosion of C. sinica.…”