1992/12/21 by F. Holzinger, Christoph Frick, Michaël Wink · 1 citation
Agricultural and Biological Sciences · Chemistry · #Botanical Research and Chemistry #Plant and animal studies #Plant Parasitism and Resistance #Danaus #Manduca sexta #Ouabain #Monarch butterfly #Histidine #Asparagine #Biology #Biochemistry #Cardiac glycoside #Amino acid #Threonine #Glycoside #Chemistry #Lepidoptera genitalia #Stereochemistry #Insect #Serine #Botany #Phosphorylation
paper · pdf · doi:10.1016/0014-5793(92)81530-y
openalex publication_date 1992/12/21 · openalex created_date 2016/06/24 · openalex updated_date 2026/07/28
The Monarch (Danaus plexippus) sequesters cardiac glycosides for its chemical defence against predators. Larvae and adults of this butterfly are insensitive towards dietary cardiac glycosides, whereas other Lepidoptera, such as Manduca sexta and Creatonotos transiens are sensitive and intoxicated by ouabain. Ouabain inhibits the Na+,K(+)-ATPase by binding to its alpha-subunit. We have amplified and cloned the DNA sequence encoding the respective ouabain binding site. Instead of the amino acid asparagine at position 122 in ouabain-sensitive insects, the Monarch has a histidine in the putative ouabain binding site, which consists of about 12 amino acids. This change may explain the ouabain insensitivity.