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: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: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:To identify specific gene networks induced in host roots by C. geophilum, we inoculated seedlings of Scots pine simultaneously with C. geophilum and either Suillus granulatus or Rhizopogon roseolus, two common ECM fungi associated to pines. We then measured the differential expression of Scots pine genes in the respective mycorrhizas using oligoarrays. We performed 14 hybridizations (NimbleGen) with samples derived from Pinus sylvestris mycorrhiza with Cenococcum geophilum, Rhizopogon roseolus or Suillus granulatus (3 biological replicates each), as well as from non-mycorrhizal control roots (two replicates). Only the Pinus-derived sequences from the array were considered for this analysis. All samples were labeled with Cy3.
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:The significant morphological differences observed during embryo development in angiosperms and gymnosperms are expected to be the result of a differential control of gene expression. We used a loblolly pine (Pinus taeda) cDNA microarray to analyze global transcriptional changes along zygotic embryogenesis in maritime pine (Pinus pinaster). A time-course analysis of the data obtained from the five embryo developmental groups used in this study led to the identification of 4,645 genes whose expression varied along P. pinaster embryogenesis. These transcripts were clustered into six distinct expression profiles. The grouping of these profiles in early, mid-embryogenesis and embryo maturation, according to the developmental period where most of the sequences were up-regulated, evidenced that characteristic transcriptional changes are associated to each developmental period. The application of a cut-off value of 1.95-fold change led to the identification of 1,838 differentially expressed transcripts that were categorized by biological process. Metabolism, interaction with the environment, oxidation-reduction and transport were some of the most represented categories. During early embryogenesis genes putatively involved in phytohormone-mediated signaling were identified, whereas in middle stages the overrepresented genes could be associated with cotyledon formation and induction of somatic embryogenesis. Genes associated with the synthesis of storage products were up-regulated in the latest stages of pine embryo development. It was also during this developmental period that the largest number of sequences putatively encoding transcription factors was identified.