dc.contributor.author
Steppuhn, Anke
dc.contributor.author
Gaquerel, Emmanuel
dc.contributor.author
Baldwin, Ian T.
dc.date.accessioned
2018-06-08T10:40:43Z
dc.date.available
2018-01-22T13:23:55.937Z
dc.identifier.uri
https://refubium.fu-berlin.de/handle/fub188/20873
dc.identifier.uri
http://dx.doi.org/10.17169/refubium-24172
dc.description.abstract
Background: Plant fatty acid α-dioxygenases (α-DOX) are oxylipin-forming
enzymes induced by biotic and abiotic stresses, which also participate in
developmental processes. In Nicotiana attenuata, herbivory strongly induces
the expression of an α-dox1 gene. To determine its role, we silenced its
expression using Agrobacterium-mediated plant transformation with an inverted
repeat construct. More than half of the transformed lines showed a severe
dwarf growth phenotype that was very similar to the phenotype of tomato plants
mutated at a second α-dox isoform. This led us to identify the corresponding
α-dox2 gene in N. attenuata and examine the regulation of both α-dox genes as
well as the consequences of their silencing in plant development and anti-
herbivore defense. Results: The transformed lines exhibiting a dwarf growth
phenotype are co-silenced for both α-dox genes resulting in a nearly complete
suppression of α-DOX activity, which is associated with increases in ABA, JA
and anthocyanin levels, all metabolic signatures of oxidative stress. The
other lines, only silenced for α-dox1, developed similarly to wild-type
plants, exhibited a 40% reduction of α-DOX activity resulting in a 50%
reduction of its main product in planta (2-HOT) and showed no signs of
oxidative stress. In contrast to α-dox1, the expression of α-dox2 gene is not
induced by wounding or elicitors in the oral secretions of Manduca sexta.
Instead, α-dox2 is expressed in roots and flowers which lack α-dox1
expression, but both genes are equally regulated during leaf maturation. We
transiently silenced α-dox gene copies with gene-specific constructs using
virus induced gene silencing and determined the consequences for plant
development and phytohormone and 2-HOT levels. While individual silencing of
α-dox1 or α-dox2 had no effects on plant growth, the co-suppression of both
α-dox genes decreased plant growth. Plants transiently silenced for both α-dox
genes had increased constitutive levels of JA and ABA but silencing α-dox1
alone resulted in lower M. sexta-induced levels of JA, 2-HOT and ABA.
Conclusions: Thus, both α-dox isoforms function in the development of N.
attenuata. In leaf maturation, the two α-dox genes have overlapping functions,
but only α-dox2 is involved in root and flower development and only α-dox1
functions in anti-herbivore defense.
en
dc.format.extent
15 Seiten
dc.rights.uri
http://creativecommons.org/licenses/by/2.0/
dc.subject.ddc
500 Naturwissenschaften und Mathematik::580 Pflanzen (Botanik)::583 Magnoliopsida (Zweikeimblättrige)
dc.subject.ddc
500 Naturwissenschaften und Mathematik::570 Biowissenschaften; Biologie::571 Physiologie und verwandte Themen
dc.title
The two α-dox genes of Nicotiana attenuata: overlapping but distinct functions
in development and stress responses
dc.type
Wissenschaftlicher Artikel
dcterms.bibliographicCitation
BMC Plant Biology 10 (2010), 171
dcterms.bibliographicCitation.doi
10.1186/1471-2229-10-171
dcterms.bibliographicCitation.url
http://doi.org/10.1186/1471-2229-10-171
refubium.affiliation
Biologie, Chemie, Pharmazie
de
refubium.affiliation.other
Institut für Biologie
refubium.mycore.fudocsId
FUDOCS_document_000000028848
refubium.note.author
Der Artikel wurde in einer Open-Access-Zeitschrift publiziert.
refubium.resourceType.isindependentpub
no
refubium.mycore.derivateId
FUDOCS_derivate_000000009353
dcterms.accessRights.openaire
open access
dcterms.isPartOf.issn
1471-2229