Evidence of a hemolymph-born factor that induces onset of maturation in Manduca sexta larvae

Bryan R. Helm, Goggy Davidowitz

Research output: Contribution to journalArticle

6 Citations (Scopus)

Abstract

Insect metamorphosis is a complex developmental transition determined and coordinated by hormonal signaling that begins at a critical weight late in the larval phase of life. Even though this hormonal signaling is well understood in insects, the internal factors that are assessed at the critical weight and that drive commitment to metamorphosis have remained unresolved in most species. The critical weight may represent either an autonomous decision by the neuroendocrine system without input from other developing larval tissues, or an assessment of developmental thresholds occurring throughout the body that are then integrated by the neuroendocrine tissues. The latter hypothesis predicts that there could be one or more developmental threshold signals that originate from developing tissues and ultimately induce the onset of metamorphosis. However, there is no evidence for such a signal in the organisms for which the critical weight is well described. Here we test for the evidence of this factor in Manduca sexta (Lepidoptera: Sphingidae) by transferring hemolymph from individuals that are either post- or pre-critical weight into pre-critical weight 5<sup>th</sup> instar larvae. We found that hemolymph from a post-critical weight donor induces a shortening of development time, though the mass at pupation is unaffected. This suggests that metamorphic commitment occurring at the critical weight is at least partially coordinated by signaling from developing tissues via a hemolymph-borne signaling factor.

Original languageEnglish (US)
Pages (from-to)78-86
Number of pages9
JournalJournal of Insect Physiology
Volume78
DOIs
StatePublished - Jul 1 2015

Fingerprint

Manduca
Hemolymph
Manduca sexta
hemolymph
Larva
Weights and Measures
larvae
metamorphosis
Insects
Sphingidae
neurosecretory system
Neurosecretory Systems
insects
Lepidoptera
pupation
shortenings
instars
tissues
organisms

Keywords

  • Body size
  • Critical weight
  • Development time
  • Developmental regulation
  • Manduca sexta
  • Metamorphosis

ASJC Scopus subject areas

  • Insect Science
  • Physiology

Cite this

Evidence of a hemolymph-born factor that induces onset of maturation in Manduca sexta larvae. / Helm, Bryan R.; Davidowitz, Goggy.

In: Journal of Insect Physiology, Vol. 78, 01.07.2015, p. 78-86.

Research output: Contribution to journalArticle

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