Changes in cytokinins are sufficient to alter developmental patterns of defense metabolites in Nicotiana attenuata

0475960 - ÚEB 2018 RIV US eng J - Journal Article
Bruetting, C. - Schaefer, N. - Vaňková, Radomíra - Gase, K. - Baldwin, I.T. - Meldau, S.
Changes in cytokinins are sufficient to alter developmental patterns of defense metabolites in Nicotiana attenuata.
Plant Journal. Roč. 89, č. 1 (2017), s. 15-30. ISSN 0960-7412. E-ISSN 1365-313X
R&D Projects: GA MŠMT LD14120
Institutional support: RVO:61389030
Keywords : proteinase-inhibitor production * plant defense * arabidopsis-thaliana * leaf senescence * insect interactions * tobacco plants * jasmonic acid * manduca-sexta * cis-zeatin * responses * cytokinins * optimal defense * herbivores * inducible defense * Nicotiana attenuata * Manduca sexta * plant development * immunosenescence * phytohormones
OECD category: Plant sciences, botany
Impact factor: 5.775, year: 2017

Plant defense metabolites are well known to be regulated developmentally. The optimal defense (OD) theory posits that a tssue's fitness values and probability of attack should determine defense metabolite allocations. Young leaves are expected to provide a larger fitness value to the plant, and therefore their defense allocations should be higher when compared with older leaves. The mechanisms that coordinate development with defense remain unknown and frequently confound tests of the OD theory predictions. Here we demonstrate that cytokinins (CKs) modulate ontogeny-dependent defenses in Nicotiana attenuata. We found that leaf CK levels highly correlate with inducible defense expressions with high levels in young and low levels in older leaves. We genetically manipulated the developmental patterns of two different CK classes by using senescence- and chemically inducible expression of CK biosynthesis genes. Genetically modifying the levels of different CKs in leaves was sufficient to alter ontogenic patterns of defense metabolites. We conclude that the developmental regulation of growth hormones that include CKs plays central roles in connecting development with defense and therefore in establishing optimal patterns of defense allocation in plants.
Permanent Link: http://hdl.handle.net/11104/0272634