Molecular basis for the insensitivity of the Monarch (Danaus plexippus) to cardiac glycosides

FEBS Letters

Wink, Michael¹  Frick, Christoph¹  Holzinger, Ferdinand¹ 

[1] Institut für Pharmazeutische Biologie, Universiät Heidelberg, Im Neuenheimer Feld 364, D-6900 Heidelberg, Germany

关键词: Danaus plexippus;    Ouabain insensitivity;    Na+;    K+-ATPase;    Binding site;    Nucleotide sequence;   

DOI  :  10.1016/0014-5793(92)81530-Y

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

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. Ouiabain inhibits the Na⁺,K⁺-ATPase by binding to its α-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.

【 授权许可】

Unknown