Skip to main content
Fig. 2 | BMC Plant Biology

Fig. 2

From: Chloroplast gene expression level is negatively correlated with evolutionary rates and selective pressure while positively with codon usage bias in Ophioglossum vulgatum L

Fig. 2

dN (nonsynonymous substitution rate), dS (synonymous substitution rate), dN/dS (selective pressure, ω) and codon usage bias analysis results. (a) Distribution and correlation (Spearman’s rank correlation coefficient) of dN, dS, and dN/dS in conserved chloroplast genes (** represents P < 0.01. *** represents P < 0.001). (b) The boxplot of dN, dS, and dN/dS distribution of chloroplast genes with three different functions (photosynthesis-related genes, genetic system-related genes and other protein-coding genes). (c) Boxplot of GC content variation in different codon positions. GC content at the first base (GC1); GC content at the second base position (GC2); the GC content at the third base position of codons (GC3); the overall GC content (GC). The orange dots represent outliers and the white represent mean values. (d) RSCU (relative synonymous codon usage) value of amino acid and codons. Different colors of columns represent different codons encoding the same amino acid. The Codons in white font were the high-frequency codons

Back to article page