Project description:Genotyping studies suggest that there is genetic variability among P. gingivalis strains, however the extent of variability remains unclear, and the regions of variability have only partially been identified. We previously used heteroduplex analysis of the ribosomal operon intergenic spacer region (ISR) to type P. gingivalis strains in several diverse populations, identifying 6 predominant heteroduplex types and many minor ones. In addition we used ISR sequence analysis to determine the relatedness of P. gingivalis strains to one another, and demonstrated a link between ISR sequence phylogeny and the disease-associated phenotype of P. gingivalis strains. The availability of whole genome microarrays based on the genomic sequence of strain W83 has allowed a more comprehensive analysis of P. gingivalis strain variability, using the entire genome. The objectives of this study were to define the phylogeny of P. gingivalis strains using the entire genome, to compare the phylogeny based on genome content to the phylogeny based on a single locus (ISR), and to identify genes that are associated with the strongly disease-associated strain W83 that could be important for virulence. Keywords: Comparative genomic hybridization
2008-10-09 | GSE13128 | GEO
Project description:Comparative analysis of whole genome duplication across the salmonid phylogeny
Project description:Genotyping studies suggest that there is genetic variability among P. gingivalis strains, however the extent of variability remains unclear, and the regions of variability have only partially been identified. We previously used heteroduplex analysis of the ribosomal operon intergenic spacer region (ISR) to type P. gingivalis strains in several diverse populations, identifying 6 predominant heteroduplex types and many minor ones. In addition we used ISR sequence analysis to determine the relatedness of P. gingivalis strains to one another, and demonstrated a link between ISR sequence phylogeny and the disease-associated phenotype of P. gingivalis strains. The availability of whole genome microarrays based on the genomic sequence of strain W83 has allowed a more comprehensive analysis of P. gingivalis strain variability, using the entire genome. The objectives of this study were to define the phylogeny of P. gingivalis strains using the entire genome, to compare the phylogeny based on genome content to the phylogeny based on a single locus (ISR), and to identify genes that are associated with the strongly disease-associated strain W83 that could be important for virulence. Keywords: Comparative genomic hybridization Comparative genomic analysis of 7 clinically prevalent P. gingivalis strains was performed, using whole genome microarrays based on the sequence of strain W83. Strain W83 was the reference strains and there were 6 test strains. Flip-dye replicates were performed.
Project description:<p>The section <em>Oleifera</em> (Theaceae) has attracted attention for the high levels of unsaturated fatty acids found in its seeds. Here, we report the chromosome-scale genome of the sect. <em>Oleifera</em> using diploid wild <em>Camellia lanceoleosa</em> with a final size of 3.00 Gb and an N50 scaffold size of 186.43 Mb. Repetitive sequences accounted for 80.63% and were distributed unevenly across the genome. <em>Camellia lanceoleosa</em> underwent a whole-genome duplication event approximately 65 million years ago (65 Mya), prior to the divergence of <em>C</em>. <em>lanceoleosa</em> and <em>Camellia sinensis</em> (approx. 6-7 Mya). Syntenic comparisons of these two species elucidated the genomic rearrangement, appearing to be driven in part by the activity of transposable elements. The expanded and positively selected genes in <em>C</em>. <em>lanceoleosa</em> were significantly enriched in oil biosynthesis, and the expansion of homomeric <em>acetyl-coenzyme A carboxylase</em> (<em>ACCase</em>) genes and the seed-biased expression of genes encoding heteromeric ACCase, diacylglycerol acyltransferase, glyceraldehyde-3-phosphate dehydrogenase and stearoyl-ACP desaturase could be of primary importance for the high oil and oleic acid content found in <em>C. lanceoleosa</em>. Theanine and catechins were present in the leaves of <em>C</em>. <em>lanceoleosa</em>. However, caffeine can not be dectected in the leaves but was abundant in the seeds and roots. The functional and transcriptional divergence of genes encoding SAM-dependent <em>N</em>-methyltransferases may be associated with caffeine accumulation and distribution. Gene expression profiles, structural composition and chromosomal location suggest that the late-acting self-incompatibility of <em>C. lanceoleosa</em> is likely to have favoured a novel mechanism co-occurring with gametophytic self-incompatibility. This study provides valuable resources for quantitative and qualitative improvements and genome assembly of polyploid plants in sect. <em>Oleifera</em>.</p>
Project description:Genome-wide SNP genotyping array can genotyped SNP highthroughly. It can be used in many aspects, such as phylogeny relationships, genome-wide association studies, copy number identification.
Project description:The evolution of gene body methylation (gbM) and the underlying mechanism is poorly understood. By pairing the largest collection of CHROMOMETHYLTRANSFERASE (CMT) sequences (773) and methylomes (72) across land plants and green algae we provide novel insights into the evolution of gbM and its underlying mechanism. The angiosperm- and eudicot-specific whole genome duplication events gave rise to what are now referred to as CMT1, 2 and 3 lineages. CMTε, which includes the eudicot-specific CMT1 and 3, and orthologous angiosperm clades, is essential for the perpetuation of gbM in angiosperms, implying that gbM evolved at least 236 MYA. Independent losses of CMT1, 2 and 3 in eudicots, and CMT2 and CMTmonocot+magnoliid in monocots suggests overlapping or fluid functional evolution. The resulting gene family phylogeny of CMT transcripts from the most diverse sampling of plants to date redefines our understanding of CMT evolution and its evolutionary consequences on DNA methylation.