Root proteome and metabolome reveal a high nutritional dependency of aluminium in Qualea grandiflora Mart. (Vochysiaceae)

Abstract

The relationship between aluminium (Al) and plants has been investigated for a long time. Al is typically harmful to plants, however Qualea grandiflora Mart., a compulsory accumulator of this metal, may benefit from it. To understand this peculiarity, proteomic and metabolite profiling analyses were carried out to investigate, at physiological, metabolic, and molecular levels, the relevance of Al for this species. Qualea grandiflora plants were grown with MS medium with or without Al-supplementation for 120 days. Metabolite profiling using GC-MS and growth analysis were conducted to evaluate the biochemical and physiological effects of Al. Concomitantly, root proteins were extracted, identified and quantified using label-free LC-MS/MS. Al-starved Q. grandiflora plants had shorter shoots, roots, lower biomass, and chlorotic leaves. Furthermore, there was a high coherence between proteomic and metabolomic data. Al was critical for cell wall and lignin syntheses, genetic information processing, and organic acid metabolism. Also, Al might help P uptake in this plant. Qualea grandiflora plants needed Al to grow and develop properly. Moreover, there was a good match between the data from physiological/metabolic analyses and the upregulated metabolic pathways indicated by proteome investigation. Hence, we propose that Q. grandiflora root metabolism is highly dependent on Al.