Project description:Analysis of microbial community composition in arctic tundra and boreal forest soils using serial analysis of ribosomal sequence tags (SARST). Keywords: other
Project description:It has long been recognized that species occupy a specific ecological niche within their ecosystem. The ecological niche is defined as the number of conditions and resources that limit species distribution. Within their ecological niche, species do not exist in a single physiological state but in a number of states we call the Natural Operating Range. In this paper we link ecological niche theory to physiological ecology by measuring gene expression levels of collembolans exposed to various natural conditions. The soil-dwelling collembolan Folsomia candida was exposed to 26 natural soils with different soil characteristics (soil type, land use, practice, etc). The animals were exposed for two days and gene expression levels were measured. The main factor found to regulate gene expression was the soil type (sand or clay), in which 18.5% of the measured genes were differentially expressed. Gene Ontology analysis showed animals exposed to sandy soils experience general stress, affecting cell homeostasis and replication. Multivariate analysis linking soil chemical data to gene expression data revealed that soil fertility influences gene expression. Land-use and practice had less influence on gene expression; only forest soils showed a different expression pattern. A variation in gene expression variation analysis showed overall low variance in gene expression. The large difference in response to soil type was caused by the soil physicochemical properties where F. candida experiences clay soils and sandy soils as very different from each other. This collembolan prefers fertile soils with high organic matter content, as soil fertility was found to correlate with gene expression and animals exposed to sandy soils (which, in general, have lower organic matter content) experience more general stress. Finally, we conclude that there is no such thing as a fixed physiological state for animals in their ecological niche and the boundary between the ecological niche and a stressed state depends on the genes/pathways investigated.
Project description:Bamboo represents the only major lineage of grasses that is native to forests and is one of the most important non-timber forest products in the world. Moso bamboo is a large woody bamboo that has ecological, economic and cultural value in Asia and accounts for ~70% of the total bamboo growth area (Peng et al., 2013). In the aspect of epigenetics of Moso bamboo,the total genomic DNA methylation rates in Moso bamboo at different chronological ages were significantly different (Yuan et al., 2014). Those show that the flowering of Moso bamboo are closely related to epigenetic modification. However, DNA methylation in single base resolution has never been reported in moso bamboo. In this study, leaves from three-week bamboo, one-year bamboo, flower in next year bamboo, flowering bamboo and Flower florets was used for bisulfite sequencing (BS-seq), and RNA-Seq. Genome-wide methylation profile and gene expression analysis were constructed to reveal the factors to regualte the phase transition from vegetative to reproductive growth in moso bamboo.
Project description:Bamboo represents the only major lineage of grasses that is native to forests and is one of the most important non-timber forest products in the world. Moso bamboo is a large woody bamboo that has ecological, economic and cultural value in Asia and accounts for ~70% of the total bamboo growth area (Peng et al., 2013). In the aspect of epigenetics of Moso bamboo,the total genomic DNA methylation rates in Moso bamboo at different chronological ages were significantly different (Yuan et al., 2014). Those show that the flowering of Moso bamboo are closely related to epigenetic modification. However, DNA methylation in single base resolution has never been reported in moso bamboo. In this study, leaves from three-week bamboo, one-year bamboo, flower in next year bamboo, flowering bamboo and Flower florets was used for bisulfite sequencing (BS-seq), and RNA-Seq. Genome-wide methylation profile and gene expression analysis were constructed to reveal the factors to regualte the phase transition from vegetative to reproductive growth in moso bamboo.
Project description:It has long been recognized that species occupy a specific ecological niche within their ecosystem. The ecological niche is defined as the number of conditions and resources that limit species distribution. Within their ecological niche, species do not exist in a single physiological state but in a number of states we call the Natural Operating Range. In this paper we link ecological niche theory to physiological ecology by measuring gene expression levels of collembolans exposed to various natural conditions. The soil-dwelling collembolan Folsomia candida was exposed to 26 natural soils with different soil characteristics (soil type, land use, practice, etc). The animals were exposed for two days and gene expression levels were measured. The main factor found to regulate gene expression was the soil type (sand or clay), in which 18.5% of the measured genes were differentially expressed. Gene Ontology analysis showed animals exposed to sandy soils experience general stress, affecting cell homeostasis and replication. Multivariate analysis linking soil chemical data to gene expression data revealed that soil fertility influences gene expression. Land-use and practice had less influence on gene expression; only forest soils showed a different expression pattern. A variation in gene expression variation analysis showed overall low variance in gene expression. The large difference in response to soil type was caused by the soil physicochemical properties where F. candida experiences clay soils and sandy soils as very different from each other. This collembolan prefers fertile soils with high organic matter content, as soil fertility was found to correlate with gene expression and animals exposed to sandy soils (which, in general, have lower organic matter content) experience more general stress. Finally, we conclude that there is no such thing as a fixed physiological state for animals in their ecological niche and the boundary between the ecological niche and a stressed state depends on the genes/pathways investigated. Test animals were exposed to 26 natural soils + 2 control soils. 4 biological replicates per soil containing 25 grams of soil and 30 23-day-old animals per replicate, RNA was isolated after two days of exposure. for the micro-array hybridization design we made use of an interwoven loop design. from the four replicates per soil two were labeled with Cy3 and 2 with Cy5. It was made sure that now two replicates of the same soil were ever hybridized against the same soil.