Project description:The pinewood nematode, Bursaphelenchus xylophilus, the pine wilt disease's causal agent, is a migratory endoparasitic nematode skilled to feed on pine tissues and on fungi that colonize the trees. In order to study B. xylophilus secretomes under the stimulus of pine species with different susceptibility to disease, nematodes were exposed to aqueous pine extracts from Pinus pinaster (high susceptible host) and P. pinea (low susceptible host). Sequential windowed acquisition of all theoretical mass spectra (SWATH-MS) was used to determine relative changes in protein amounts between B. xylophilus secretions, and a total of 776 secreted proteins were quantified in both secretomes.
Project description:Masson pine (Pinus massoniana) has evolved some adaptations for growth in low P soils. To elucidate these mechanisms, we investigated global gene expression profiles of the masson pine responding to long-term phosphorus starvation and different Pi levels (P1, 0.01 mM P; P2, 0.06 mM P). Analysis used phosphorus-sufficient treatment RNA as control samples for comparison to the experimental samples (P1 and P2) taken at 12, 24, 48 and 60 day. Indirect comparisons were made across multiple arrays with raw data pulled from different channels for data analysis and comparison to the control data.
Project description:There are several issues complicating somatic embryogenesis in conifers, for instance the low initiation frequency, the weak maturation capacity, and the loss of an embryogenic potential after a prolonged cultivation. The aim of our study was to clarify molecular details of the this process in the tree Pinus nigra Arn. We performed comparative proteomic analysis based on the two-dimensional gel electrophoresis in 2 genotypes coded 362 and 366 of: 1) proliferating embryogenic tissues (E) initiated from immature zygotic embryos, 2) non-embryogenic calli (NEC) started from cotyledons of somatic seedlings, 3) embryogenic tissues that lost the maturation capacity (E-L). Pine tissues showed distinct morphologic features: a) E362 and E366 were characterized by the presence of early bipolar structures capable of maturation and plantlet regeneration; b) NEC362 and NEC366 were composed of round shaped cells without any organisation; c) for E-L362 and E-L366 the long-term culture of initially embryogenic tissues resulted in the disorganisation of early bipolar structures. We found 24 differentially accumulated protein spots common for both genotypes after comparison of E versus NEC.
Project description:Masson pine (Pinus massoniana) has evolved some adaptations for growth in low P soils. To elucidate these mechanisms, we investigated global gene expression profiles of the masson pine responding to long-term phosphorus starvation and different Pi levels (P1, 0.01 mM P; P2, 0.06 mM P).
Project description:In conifer forests of Northern Europe, a pathogenic fungus Heterobasidion annosum attacks the roots of Scots pine and causes mortality. Trees with infection grow slower and produce less timber with reduced quality. Despite applied control methods, such as switching tree species to a non-host species, or stump treatment, root and butt rot continues to be a serious forest health problem. Disease resistance breeding is a less-applied control method which has potential to improve tree health. However, neither conifer genotypes with absolute resistance to Heterobasidion sp. nor robust selection markers for resistance breeding have been found. We studied the responses of various Scots pine genotypes to Heterobasidion annosum infection and mechanic damage in drained peatland. Stems and roots of mature naturally regenerated Scots pine trees growing in drained peatland were either artificially infected with H. annosum or wounded and inoculated with sterile inoculum. Untreated trees from the study sites served as controls. Responses of different Scots pine genotypes to pathogen infection as determined by lesion size were recorded from samples harvested four months after inoculation, and least susceptible and highly susceptible genotypes were selected from the study material. Analysis of terpenoids from both least susceptible and highly susceptible pine genotypes by gas chromatography coupled with mass spectrometry indicates that some monoterpenes and sesquiterpenes are differentially induced depending on the susceptibility level. Transcriptomic microarray analysis was therefore conducted with RNA from stems of the least susceptible and highly susceptible Scots pine genotypes. Gene expression data from cDNA microarray were analysed by comparisons between the treatments, and the genotypes with different resistance level. The aim of the study is to highlight transcripts specific to differing levels of susceptibility.
Project description:In the present study, the miRNA expression changes in the maritime pine roots from seedlings of one-month old under different levels of ammonium nutrition was analyzed.
Project description:Current projections for global climate change predict an increase in the intensity and frequency of heat waves and droughts. The improvement in our understanding of the mechanisms of how trees precisely can predict environmental threats and cope with these stresses benefits our natural selection or genetic improvement to the maintenance of forest sustainability. In this work, we investigate the metabolic changes in heat and drought combined stress in Pinus pinaster plantlets. Maritime pine is a coniferous tree with native populations distributed across the European Atlantic and Mediterranean basins and the north of Africa ranging from cool moist to warm dry climates. This species shows high plasticity and a contrasting adaptive capacity and resilience. This plasticity in the response to stress exposure may be associated with a differential ability to modulate their secondary metabolism. For this reason, the current study aims to investigate the gradual and synergetic metabolomic response using liquid chromatography coupled to mass spectrometry (LC-MS) based on untargeted metabolomic profiling of four stress levels. These metabolic profiles were supported by physiological and biochemical determinations. Our results showed that the metabolic profiles induced by low-stress exposition represent an adaptive conditioning mode with metabolome changes that help seedlings to cope with upcoming stress. The metabolism pathways involved in this response were mainly included in amino acid metabolism and carbohydrate metabolism leading to an enhanced accumulation of phenolics, flavonoids, and terpenoids. However, when the plantlets were exposed to higher-stress exposition, the secondary metabolites that starred the response are more complex and decorated, such as alkaloids, lignans, and glycosyloxyflavones. Those changes could help to maintain homeostasis and control the response magnitude on establishing and facilitating the plantlets’ survival. Overall, our findings provide new insights into the responsive mechanisms of the maritime pine under heat and drought stress in terms of metabolic profiles.
Project description:To better understand the molecular bases of resin production, a major source of terpenes for industry, the transcriptome of adult Pinus elliottii var. elliottii (slash pine) trees under field commercial resinosis was obtained.
Project description:To study the alteration pattern and defensive response mechanism triggered by herbivorous feeding stimuli under natural conditions, we built a biological model of the interrelationship between the Chinese pine (Pinus tabuliformis Carr.) and the Chinese pine caterpillar (Dendrolimus tabulaeformis Tsai et Liu) within their native habitat. We integrated proteomic and phosphoproteomic data, normalized the results, and combined them with bioinformatics to evaluate and analyze variations in phosphoproteomics in pine needles' response to the caterpillar's feeding stimulus. We systematically identified differentially significant phosphorylated proteins implicated in the pine's defense mechanism against caterpillar stress. Furthermore, we predicted upstream kinases of phosphorylation sites and their activities. Similarly, through an analysis of the Motif patterns of phosphorylated proteins, Mfuzz clustering of phosphorylation sites, kinase regulatory networks and functional modules of phosphorylated protein interaction networks in response to stress within pine, we can investigate the mechanisms behind resistance formation and regulation of caterpillar feeding incentives in pine. The identification results of partially phosphorylated proteins were additionally confirmed through PRM technology. Furthermore, genes upstream of differentially expressed proteins were validated through RT-qPCR detection.