A novel method for determination of the 15N isotopic composition of Rubisco in wheat plants exposed to elevated atmospheric carbon dioxide. Issue 2 (5th November 2014)

• Record Type: Journal Article
• Authors: Aranjuelo, Iker; Molero, Gemma; Avice, Jean Christophe; Bourguignon, Jacques
• Is Part Of: Physiologia plantarum. Volume 153:Issue 2(2015:Feb.)
• Page Start: 195
• Page End: 203
• Publication Date: 2014-11-05
• Subjects: Plant physiology -- Periodicals; 571.2
• DOI: 10.1111/ppl.12294
• Languages: English
• ISSNs: 0031-9317

Abstract

<abstract abstract-type="main" id="ppl12294-abs-0001"> <title> <x xml:space="preserve">Abstract</x> </title> <p id="ppl12294-para-0001">Although ribulose‐1, 5‐bisphosphate carboxylase/oxygenase (Rubisco) is mostly known as a key enzyme involved in CO₂ assimilation during the Calvin cycle, comparatively little is known about its role as a pool of nitrogen storage in leaves. For this purpose, we developed a protocol to purify Rubisco that enables later analysis of its ¹⁵N isotope composition (δ¹⁵N) at the natural abundance and ¹⁵N‐labeled plants. In order to test the utility of this protocol, durum wheat (<italic>Triticum durum</italic> var. Sula) exposed to an elevated CO₂ concentration (700 vs 400 µmol mol⁻¹) was labeled with K¹⁵NO₃ (enriched at 2 atom %) during the ear development period. The developed protocol proves to be selective, simple, cost effective and reproducible. The study reveals that ¹⁵N labeling was different in total organic matter, total soluble protein and the Rubisco fraction. The obtained data suggest that photosynthetic acclimation in wheat is caused by Rubisco depletion. This depletion may be linked to preferential nitrogen remobilization from Rubisco toward grain filling.</p> </abstract>