title: Energy and lipid metabolism during direct and diapause development in a pierid butterfly.
abstract: Diapause is a fundamental component of the life cycle in the majority of insects living in environments characterized by strong seasonality. The present study addresses poorly understood associations and trade-offs between endogenous diapause duration, thermal sensitivity of development, energetic cost of development and cold tolerance. Diapause intensity, metabolic rate trajectories and lipid profiles of directly developing and diapausing animals were studied using pupae and adults of Pieris napi butterflies from a population in which endogenous diapause has been well studied. Endogenous diapause was terminated after 3 months and termination required chilling. Metabolic and post-diapause development rates increased with diapause duration, while the metabolic cost of post-diapause development decreased, indicating that once diapause is terminated, development proceeds at a low rate even at low temperature. Diapausing pupae had larger lipid stores than the directly developing pupae, and lipids constituted the primary energy source during diapause. However, during diapause, lipid stores did not decrease. Thus, despite lipid catabolism meeting the low energy costs of the diapausing pupae, primary lipid store utilization did not occur until the onset of growth and metamorphosis in spring. In line with this finding, diapausing pupae contained low amounts of mitochondria-derived cardiolipins, which suggests a low capacity for fatty acid β-oxidation. While ontogenic development had a large effect on lipid and fatty acid profiles, only small changes in these were seen during diapause. The data therefore indicate that the diapause lipidomic phenotype is developed early, when pupae are still at high temperature, and retained until post-diapause development.
authors.affiliation: Department of Zoology, Stockholm University, SE-10691 Stockholm, Sweden philipp.lehmann@zoologi.su.se.
authors.forename: Philipp
authors.identifier: 0000-0001-8344-6830
authors.initials: P
authors.lastname: Lehmann
authors.affiliation: Department of Zoology, Stockholm University, SE-10691 Stockholm, Sweden.
authors.forename: Peter
authors.initials: P
authors.lastname: Pruisscher
authors.affiliation: Department of Zoology, Stockholm University, SE-10691 Stockholm, Sweden.
authors.forename: Diana
authors.initials: D
authors.lastname: Posledovich
authors.affiliation: Department of Zoology, Stockholm University, SE-10691 Stockholm, Sweden.
authors.forename: Mikael
authors.initials: M
authors.lastname: Carlsson
authors.affiliation: Department of Biosciences, University of Helsinki, FI-00014 Helsinki, Finland.
authors.forename: Reijo
authors.initials: R
authors.lastname: Käkelä
authors.affiliation: Department of Biosciences, University of Helsinki, FI-00014 Helsinki, Finland.
authors.forename: Patrik
authors.initials: P
authors.lastname: Tang
authors.affiliation: Department of Zoology, Stockholm University, SE-10691 Stockholm, Sweden.
authors.forename: Sören
authors.initials: S
authors.lastname: Nylin
authors.affiliation: Department of Zoology, Stockholm University, SE-10691 Stockholm, Sweden.
authors.forename: Christopher W
authors.initials: CW
authors.lastname: Wheat
authors.affiliation: Department of Zoology, Stockholm University, SE-10691 Stockholm, Sweden.
authors.forename: Christer
authors.initials: C
authors.lastname: Wiklund
authors.affiliation: Department of Zoology, Stockholm University, SE-10691 Stockholm, Sweden.
authors.forename: Karl
authors.initials: K
authors.lastname: Gotthard
mesh_terms: D000818:Animals; D001481:Basal Metabolism / Q000502:physiology; D001835:Body Weight; D002080:Butterflies / Q000378:metabolism*; D019069:Cell Respiration; D064666:Diapause, Insect / Q000502:physiology*; D004734:Energy Metabolism; D005227:Fatty Acids / Q000032:analysis; D050356:Lipid Metabolism; D055442:Metabolome; D055432:Metabolomics; D025341:Principal Component Analysis; D013696:Temperature
chemical_list: D005227:Fatty Acids
keywords: Fatty acids; Lipid stores; Pieris napi; Pupa; Respirometry; Stress