Streptococcus pneumoniae in the heart subvert the host response through biofilm-mediated resident macrophage killing
Fig 5
Pneumococcal transcriptome in the heart is distinct from the blood and in vitro conditions.
(A) Two-dimensional (PC1-PC2) principal component analysis on transcriptomes of BIP, HIP, in vitro biofilm-, and in vitro planktonic TIGR4 samples. PC1 separates the in vivo conditions from the in vitro conditions. PC2 separates biofilm conditions from planktonic conditions. B) Whole transcriptome comparisons for differentially expressed genes under the above conditions presented as circular plots (Circos software, see methods). Ideogram (outer rim): Each quadrant denotes one condition with 1,969 genes ranked by their expression. Red denotes highly expressed genes, gray indicates intermediate expressed genes, and green indicates low expressed genes for each condition. Genes with counts of 0 reads across all samples were excluded. Scatter Plot (inner rim): The scatter plot illustrates the Log10 (Count Per Million-mapped- reads) values for each gene in each condition ranging from -2 (inner) to 5 (outer) in steps of 0.5. Red dots are highly expressed genes; black dots are intermediate expressed genes and green dots are low expressed genes. Links (interior): Red arcs link genes with high expression in both conditions. Green arcs connect genes with low expression in both conditions. Blue arcs link genes with low expression in one condition and high expression in another condition. A higher density of connectivity for links of same color indicates transcriptomic similarities within the pneumococcal populations isolated from the tested conditions. (C) Curve plot representation of gene expression levels for Regions of Diversity RD2, RD6 and RD12 in the BIP, HIP, in vitro biofilm-, and in vitro planktonic- TIGR4 samples. Y-axis denotes normalized expression levels (i.e. RPKMs) whereas X-axis denotes individual nucleotide location (nt coordinates) on the TIGR4 chromosome. RD corresponds to Regions of Diversity as determined by Tettelin and Hollingshead [24]. The Tpr/Phr peptide quorum sensing-signaling cassettes within the RDs are indicated as determined by Hoover et al [46]. Two pooled BIP samples (5 mice per sample), three HIP samples, three in vitro biofilms and three in vitro planktonic pneumococci samples were tested.