CHEMOECOLOGY

, Volume 10, Issue 4, pp 201–203

Molecular studies on the ouabain binding site of the Na+, K+-ATPase in milkweed butterflies

  • Dietrich Mebs
  • Richard Zehner
  • Michael Schneider

DOI: 10.1007/PL00001823

Cite this article as:
Mebs, D., Zehner, R. & Schneider, M. Chemoecology (2000) 10: 201. doi:10.1007/PL00001823

Summary.

The Na+, K+-ATPase of the Monarch butterfly (Danaus plexippus) is insensitive to the inhibition by cardiac glycosides due to an amino acid replacement: histidine instead of asparagine at position 122 of the α-subunit representing the ouabain binding site. By PCR amplification of the DNA sequence of this site, a PCR product of 270 bp was obtained from DNA extracted from Danainae species (Danaus plexippus, D. chrysippus, D. gillipus, D. philene, D. genutia, Tirumala hamata, Euploea spp., Parantica weiskei, P. melusine), Sphingidae (Daphnis nerii) and mimics of milkweed butterflies (Hypolimnas missipus, Limenitis archippus and L. arthemis, Nymphalidae). Analysis of the nucleotide sequences revealed that the single point mutation in the ouabain binding domain (AAC-Asn for CAC-His) was present only in Danaus plexippus, but not in the other species investigated. Since these milkweed butterflies also store cardenolides, other structural modifications of the Na+, K+-ATPase may have occurred or other strategies of cardenolide tolerance have been developed.

Key words. Na+– K+-ATPase – cardiac glycosides – cardenolides – Lepidoptera – Danainae – Sphingidae – Nymphalidae

Copyright information

© Birkhäuser Verlag Basel, 2000

Authors and Affiliations

  • Dietrich Mebs
    • 1
  • Richard Zehner
    • 1
  • Michael Schneider
    • 1
  1. 1.Zentrum der Rechtsmedizin, University of Frankfurt, Kennedyallee 104, D-60596 Frankfurt, Germany, e-mail: mebs@em.uni-frankfurt.deDE