Project description:Competition is a major determinant of plant community structure consisting of both species-specific and general interactions, either of which may influence competitive competency and plant abundance and size. In certain cases, competitive competency could arise from altered gene expression and plant function when an individual is confronted with new competitors. We explored competition at the molecular level by hybridizing transcripts from Centaurea maculosa (spotted knapweed), one of North America's most invasive exotic plant species, to an Arabidopsis microarray chip. Centaurea was grown in competition with Festuca idahoensis (Idaho fescue), a native grass species that generally has weak competitive effects against Centaurea; Gaillardia aristata (Indian blanketflower), a native herbaceous species that tends to be a much stronger competitor against Centaurea; or alone (control). The expression of some genes was found to be relatively uninfluenced by the type of plant neighbor, whereas other patterns of gene expression appeared to be more neighbor specific. To our knowledge, these results are the first to identify genes in an invasive plant that are induced or repressed by plant neighbors and provide a new avenue of insight into the molecular aspects of plant competitive ability. Keywords: treated vs.untreated
Project description:Competition is a major determinant of plant community structure consisting of both species-specific and general interactions, either of which may influence competitive competency and plant abundance and size. In certain cases, competitive competency could arise from altered gene expression and plant function when an individual is confronted with new competitors. We explored competition at the molecular level by hybridizing transcripts from Centaurea maculosa (spotted knapweed), one of North America's most invasive exotic plant species, to an Arabidopsis microarray chip. Centaurea was grown in competition with Festuca idahoensis (Idaho fescue), a native grass species that generally has weak competitive effects against Centaurea; Gaillardia aristata (Indian blanketflower), a native herbaceous species that tends to be a much stronger competitor against Centaurea; or alone (control). The expression of some genes was found to be relatively uninfluenced by the type of plant neighbor, whereas other patterns of gene expression appeared to be more neighbor specific. To our knowledge, these results are the first to identify genes in an invasive plant that are induced or repressed by plant neighbors and provide a new avenue of insight into the molecular aspects of plant competitive ability. Keywords: treated vs.untreated First file, Chip 508 (9-9-05) is preliminary hyb data to see if this cross species hybridization is possible using the OAR27K chip Experiment 1 (chip 508): The Arabidopsis OAR27K gene chip was hybridized with labeled cDNA probes produced from samples of Centaurea RNA at the W.M. Keck Foundation Biotechnology Resource Laboratory, Yale University. The OAR27K gene chip consists of 70-mer oligos representing approximately 27,000 genes from Arabidopsis. Leaf and root samples were reverse-transcribed into cDNA and labeled with different fluorescent dyes (Cy3 and Cy5) using the Genisphere Array 900 kit (Cat No.W500180) (Genisphere, Hatfield PA). Labeled cDNAs were hybridized to the OAR27Kchip using the Advalytix ArrayBooster DNA Microarray Incubator (Advalytix, Boston MA). Approximately 10ug of each sample was used for hybridization.Experiment 2: Hybridization and labeling followed the procedure above, except the experimental control was Centaurea plants grown alone, and the test situations were Centaurea grown with Gaillardia or Festuca neighbors. In each experiment, RNA from Centaurea grown alone was used as the control (labeled with Cy3) and RNA from Centaurea grown with a neighbor was used as the test (labeled with Cy5). Two replicates were performed for each test situation.
Project description:Competition is a major determinant of plant community structure consisting of both species-specific and general interactions, either of which may influence competitive competency and plant abundance and size. In certain cases, competitive competency could arise from altered gene expression and plant function when an individual is confronted with new competitors. We explored competition at the molecular level by hybridizing transcripts from Centaurea maculosa (spotted knapweed), one of North America's most invasive exotic plant species, to an Arabidopsis microarray chip. Centaurea was grown in competition with Festuca idahoensis (Idaho fescue), a native grass species that generally has weak competitive effects against Centaurea; Gaillardia aristata (Indian blanketflower), a native herbaceous species that tends to be a much stronger competitor against Centaurea; or alone (control). The expression of some genes was found to be relatively uninfluenced by the type of plant neighbor, whereas other patterns of gene expression appeared to be more neighbor specific. To our knowledge, these results are the first to identify genes in an invasive plant that are induced or repressed by plant neighbors and provide a new avenue of insight into the molecular aspects of plant competitive ability. Keywords: treated vs.untreated
Project description:Understanding the mechanisms underlying the establishment of invasive plants is critical in community ecology. According to a widely accepted theory, plant-soil-microbe interactions mediate the effects of invasive plants on native species, thereby affecting invasion success. However, the roles and molecular mechanisms associated with such microbes remain elusive. Using high throughput sequencing and a functional gene microarray, we found that soil taxonomic and functional microbial communities in plots dominated by Ageratina adenophora developed to benefit the invasive plant. There were increases in nitrogen-fixing bacteria and labile carbon degraders, as well as soil-borne pathogens in bulk soil, which potentially suppressed native plant growth. Meanwhile, there was an increase of microbial antagonism in the A. adenophora rhizosphere, which could inhibit pathogenicity against plant invader. These results suggest that the invasive plant A. adenophora establishes a self-reinforcing soil environment by changing the soil microbial community. It could be defined as a ‘bodyguard/mercenary army’ strategy for invasive plants, which has important insights for the mitigation of plant invasion.
Project description:Echinacea, native to the Canadian prairies and the prairie states of the United States, has a long tradition as a folk medicine for the Native Americans. Currently, Echinacea are among the top 10 selling herbal medicines in the U.S. and Europe, due to increasing popularity for the treatment of common cold and ability to stimulate the immune system. However, the genetic relationships within the species of this genus are unclear, which makes difficult the authentication of the species used for the medicinal industry. We report the construction of a novel Subtracted Diversity Array (SDA) for Echinacea species and demonstrate the potential of this array for isolating highly polymorphic sequences.
Project description:Competition is a major determinant of plant community structure consisting of both species-specific and general interactions, either of which may influence competitive competency and plant abundance and size. In certain cases, competitive competency could arise from altered gene expression and plant function when an individual is confronted with new competitors. We explored competition at the molecular level by hybridizing transcripts from Centaurea maculosa (spotted knapweed), one of North America's most invasive exotic plant species, to an Arabidopsis microarray chip. Centaurea was grown in competition with Festuca idahoensis (Idaho fescue), a native grass species that generally has weak competitive effects against Centaurea; Gaillardia aristata (Indian blanketflower), a native herbaceous species that tends to be a much stronger competitor against Centaurea; or alone (control). The expression of some genes was found to be relatively uninfluenced by the type of plant neighbor, whereas other patterns of gene expression appeared to be more neighbor specific. To our knowledge, these results are the first to identify genes in an invasive plant that are induced or repressed by plant neighbors and provide a new avenue of insight into the molecular aspects of plant competitive ability. Keywords: treated vs.untreated Files; chip 618 (12-7-05) and chip 623 (1-20-06) are replicates. One channel is root cDNA from Centaurea maculosa grown in isolation and the other channel is root cDNA from Centaurea maculosa grown with a strong competitor, Gaillardia aristata. For each chip, RNA extractions on unique biological samples were performed. Files; chip 720 (2-23-06) and chip 723 (3-17-06) are replicates. One channel is root cDNA from Centaurea maculosa grown in isolation and the other channel is root cDNA from Centaurea maculosa grown with a weak competitor, Festuca idahoensis. For each chip, RNA extractions on unique biological samples were performed.