A maize (E)-beta-caryophyllene synthase implicated in indirect defense responses against herbivores is not expressed in most American maize varieties
Tobias G Kollner, Matthias Held, Claudia Lenk, Ivan Hiltpold, Ted Turlings, Jonathan Gershenzon & Joerg Degenhardt
| Résumé |
The sesquiterpene (E)-beta-caryophyllene is emitted by maize (Zea
mays) leaves in response to attack by lepidopteran larvae like
Spodoptera littoralis and released from roots after damage by
larvae of the coleopteran Diabrotica virgifera virgifera. We
identified a maize terpene synthase, Terpene Synthase 23 (TPS23),
that produces (E)-beta-caryophyllene from farnesyl diphosphate. The
expression of TPS23 is controlled at the transcript level and
induced independently by D. v. virgifera damage in roots and S.
littoralis damage in leaves. We demonstrate that
(E)-beta-caryophyllene can attract natural enemies of both
herbivores: entomopathogenic nematodes below ground and parasitic
wasps, after an initial learning experience, above ground. The
biochemical properties of TPS23 are similar to those of
(E)-beta-caryophyllene synthases from dicotyledons but are the
result of repeated evolution. The sequence of TPS23 is maintained
by positive selection in maize and its closest wild relatives,
teosinte (Zea sp) species. The gene encoding TPS23 is active in
teosinte species and European maize lines, but decreased
transcription in most North American lines resulted in the loss of
(E)-beta-caryophyllene production. We argue that the
(E)-beta-caryophyllene defense signal was lost during breeding of
the North American lines and that its restoration might help to
increase the resistance of these lines against agronomically
important pests. |
| Mots-clés |
ROOTWORM COLEOPTERA-CHRYSOMELIDAE, INDUCED PLANT VOLATILES, COENZYME-A, REDUCTASE, ENTOMOPATHOGENIC NEMATODES, PARASITIC WASPS, ZEA-MAYS, COTESIA-MARGINIVENTRIS, ARTEMISIA-ANNUA, NATURAL ENEMIES, FLORAL TISSUES |
| Citation | Kollner, T. G., Held, M., Lenk, C., Hiltpold, I., Turlings, T., Gershenzon, J., & Degenhardt, J. (2008). A maize (E)-beta-caryophyllene synthase implicated in indirect defense responses against herbivores is not expressed in most American maize varieties. Plant Cell, 20(2), 482-494. |
| Type | Article de périodique (Anglais) |
| Date de publication | 2008 |
| Nom du périodique | Plant Cell |
| Volume | 20 |
| Numéro | 2 |
| Pages | 482-494 |