Due to massive energetic investments in woody support structures, trees are subject to unique physiological, mechanical, and ecological pressures not experienced by herbaceous plants. Despite a... Show moreDue to massive energetic investments in woody support structures, trees are subject to unique physiological, mechanical, and ecological pressures not experienced by herbaceous plants. Despite a wealth of studies exploring trait relationships across the entire plant kingdom, the dominant traits underpinning these unique aspects of tree form and function remain unclear. Here, by considering 18 functional traits, encompassing leaf, seed, bark, wood, crown, and root characteristics, we quantify the multidimensional relationships in tree trait expression. We find that nearly half of trait variation is captured by two axes: one reflecting leaf economics, the other reflecting tree size and competition for light. Yet these orthogonal axes reveal strong environmental convergence, exhibiting correlated responses to temperature, moisture, and elevation. By subsequently exploring multidimensional trait relationships, we show that the full dimensionality of trait space is captured by eight distinct clusters, each reflecting a unique aspect of tree form and function. Collectively, this work identifies a core set of traits needed to quantify global patterns in functional biodiversity, and it contributes to our fundamental understanding of the functioning of forests worldwide. Show less
Haddad, G.; Lorenzen, J.M.; Ma, H.; Haan, N. de; Seeger, H.; Zaghrini, C.; ... ; Kistler, A.D. 2021
Primary membranous nephropathy (pMN) is a leading cause of nephrotic syndrome in adults. In most cases, this autoimmune kidney disease is associated with autoantibodies against the M-type... Show morePrimary membranous nephropathy (pMN) is a leading cause of nephrotic syndrome in adults. In most cases, this autoimmune kidney disease is associated with autoantibodies against the M-type phospholipase A2 receptor (PLA2R1) expressed on kidney podocytes, but the mechanisms leading to glomerular damage remain elusive. Here, we developed a cell culture model using human podocytes and found that anti-PLA2R1-positive pMN patient sera or isolated IgG4, but not IgG4-depleted sera, induced proteolysis of the 2 essential podocyte proteins synaptopodin and NEPH1 in the presence of complement, resulting in perturbations of the podocyte cytoskeleton. Specific blockade of the lectin pathway prevented degradation of synaptopodin and NEPH1. Anti-PLA2R1 IgG4 directly bound mannose-binding lectin in a glycosylation-dependent manner. In a cohort of pMN patients, we identified increased levels of galactose-deficient IgG4, which correlated with anti-PLA2R1 titers and podocyte damage induced by patient sera. Assembly of the terminal C5b-9 complement complex and activation of the complement receptors C3aR1 or C5aR1 were required to induce proteolysis of synaptopodin and NEPH1 by 2 distinct proteolytic pathways mediated by cysteine and aspartic proteinases, respectively. Together, these results demonstrated a mechanism by which aberrantly glycosylated IgG4 activated the lectin pathway and induced podocyte injury in primary membranous nephropathy. Show less
Plants and soils from natural ecosystems harbor great diversity of soil microorganisms, which could potentially contribute to the sustainability of horticulture. The knowledge about using wild... Show morePlants and soils from natural ecosystems harbor great diversity of soil microorganisms, which could potentially contribute to the sustainability of horticulture. The knowledge about using wild plant species and soil from natural ecosystem to improve the crop health will advance the application of ecological knowledge in horticulture. In this thesis, I evaluate the possibilities of using wild plant species and grassland soil to enhance the growth and reduce the disease susceptibility of chrysanthemum through plant-soil feedback principles. Grass-conditioned inocula contributed more to chrysanthemum growth than forb- or legume-conditioned inocula, this also lead to better chrysanthemum performance under Pythium treatment. Moreover, by mixing two plant-conditioned inocula, they interacted synergistically in terms of plant health but antagonistically in terms of plant growth. The influence of plant-conditioned inocula on chrysanthemum were still significant after two successive growth cycles, but their effects tended to converge because of the overriding effect of chrysanthemum growth. Inoculating greenhouse soil conditioned by wild plant species or grassland soil to greenhouse soil did not significantly improve the negative effects of greenhouse soil on chrysanthemum growth. Olpidium brassicae was identified as a main fungal pathogen of chrysanthemum when growing in greenhouse soil. Show less
