Project description:We examine the development of the seedling roots based on two sets of data: one includes segments of the roots and one includes laser capture microdissection (LCM) root tissues.
Project description:We investigated root associated fungi in young Norway spruce (Picea abies) cuttings rooted from slow- and fast-growing trees showing variable growth rate in long-term field experiments and compared their roots’ gene expression patterns five and 18 months after adventitious root initiation. Gene expression patterns of adventitious roots could not be systematically linked with the growth phenotype at the initiation of root formation, and thus fundamental differences in the receptiveness of fungal symbionts could not be assumed.
Project description:Nicotinamide seed treatment is investigated as a method for production of robust plants. Previous studies have shown that nicotinamide promotes the plant defence system and decreases DNA methylation levels. The purpose of the present work was to learn more about the underlying molecular mechanisms. The RNA was extracted from roots of three months old Norway spruce seedlings treated at seed stage. Stress was an overrepresented biological process of upregulated genes. Stress response genes are involved in adaption to and defence against stress. Upregulated stress response genes in the seedling roots were for example transcription factors MYB77 and LHY and two chitinases. Chitinases defend against biotic stress, such as pine weevils. Epigenetic regulating genes were generally downregulated, such as DDM1 which is known to promote DNA-methylation. Previous works suggest the hypothesis that nicotinamide is a defense signal mediator, which is supported by the present study.
Project description:Conifer-specific responses to elicitation with the chemical elicitor chitosan have been investigated using a transcriptome analysis in Norway spruce using a cell suspension culture system that has been previously described (Phillips, Walter et al. 2007). This study has demonstrated that the early events following chitosan elicitation include calcium mediated signaling and an oxidative response that have not previously been described in intact trees. Keywords: stress response
Project description:In order to test Norway spruce radiosensitivity to gamma radiation, 6 days old seedlings were exposed for 48 h to 60-Co source at dose rates 1, 10, 40 or 100 mGy/h.
Project description:Photosystem II (PSII) complexes are organized into large supercomplexes with variable amounts of light-harvesting proteins (Lhcb). A typical PSII supercomplex in plants is formed by four trimers of Lhcb proteins (LHCII trimers), which are bound to the PSII core dimer via monomeric antenna proteins. However, the architecture of PSII supercomplexes in Norway spruce (Picea abies (L.) Karst.) is different, most likely due to a lack of two Lhcb proteins, Lhcb6 and Lhcb3. Interestingly, the spruce PSII supercomplex shares similar structural features with its counterpart in the green alga Chlamydomonas reinhardtii (Kouřil et al.: New Phytol. 210, 808-814, 2016). Here we present a single-particle electron microscopy study of isolated PSII supercomplexes from Norway spruce that revealed binding of a variable amount of LHCII trimers to the PSII core dimer at positions that have never been observed in any other plant species so far. The largest spruce PSII supercomplex, which was found to bind 8 LHCII trimers, is even larger than the current largest known PSII supercomplex from Chlamydomonas reinhardtii. We have also shown that the spruce PSII supercomplexes can form various types of PSII megacomplexes, which were also identified in intact grana membranes. Some of these large PSII supercomplexes and megacomplexes were identified also in Pinus sylvestris, another representative of Pinaceae family. The structural variability and complexity of LHCII organization in Pinaceae seems to be related to the absence of Lhcb6 and Lhcb3 in this family and may be beneficial for the optimization of light-harvesting under varying environmental conditions.