Pharmacologic approaches to butterfly wing patterning: sulfated polysaccharides mimic or antagonize cold shock and alter the interpretation of gradients of positional information.
Butterflies produce complex and diverse wing patterns by mechanisms that are generally unknown. We have employed a pharmacological approach to explore the molecular mechanisms of pattern formation. In a screen of over 200 compounds injected into developing Junonia coenia pupae, we identified several specific sulfated polysaccharides that caused widespread, dose-dependent effects on adult wing patterns. These compounds were well tolerated and permitted butterflies to eclose normally and take flight at moderate levels of effect. Heparin and closely related chondroitin sulfates caused stage-specific expansion of distal and proximal band systems and reduction and repatterning of eyespots. Dextran sulfate and fucoidan, whose structures are widely divergent from heparin and one another, caused contraction of distal and proximal systems, but had no effect on eyespots. Nonsulfated or nonpolymeric saccharides were without effect. Pattern alterations were indistinguishable from those reported for extreme cold shock and exposure to sodium tungstate and "molsin". When administered after cold shock or coinjected with heparin, dextran sulfate reversed all patterning effects. We suggest that the primary effect of polysaccharide treatments is to alter the interpretation of gradients of positional information along the proximodistal axis of the pupal wing.
Serfas
Michael S
MS
Howard Hughes Medical Institute, University of Wisconsin-Madison, 1525 Linden Drive, Madison WI 53706, USA.
Carroll
Sean B
SB
D000818:Animals; D019521:Body Patterning / Q000187:drug effects / Q000502:physiology; D002080:Butterflies / Q000187:drug effects* / Q000502:physiology; D002809:Chondroitin Sulfates / Q000494:pharmacology; D003080:Cold Temperature; D016264:Dextran Sulfate / Q000494:pharmacology; D006493:Heparin / Q000494:pharmacology; D006497:Heparan Sulfate / Q000494:pharmacology; D008954:Models, Biological; D010858:Pigmentation / Q000187:drug effects / Q000502:physiology; D011134:Polysaccharides / Q000494:pharmacology*; D014921:Wings, Animal / Q000187:drug effects* / Q000502:physiology
D002809:Chondroitin Sulfates; D016264:Dextran Sulfate; D006493:Heparin; D006497:Heparan Sulfate; D011134:Polysaccharides; C007789:fucoidan