FIG. 2.—

N contents in the genome, transcriptome and proteome of undomesticated and crop species. (A) Distribution of N content in the transcriptomes and (B) deviations from Chargaff's second parity rule in Arabidopsis thaliana (undomesticated) and Oryza sativa (crop). The mean, SD, standard error (SE), and sample size (number of genes) of N content distribution in (A) are A. thaliana (3.485, 0.114, 0.0007, and 26,544) and O. sativa (3.616, 0.139, 0.0006, and 54,712). The overall genomic N content was 3.680 (119 × 10⁶ bp) for A. thaliana and 3.718 (372 × 10⁶ bp) for O. sativa. In (B), the mean, SD, and SE of the difference between the N contents of the sense and antisense strands are −0.352, 0.226, and 0.001 for A. thaliana, and −0.171, 0.249, and 0.001 for O. sativa, with the whole-genome deviation close to zero in both species (A. thaliana = 0.0008 and O. sativa = 0.0002). (C) N content per amino acid side chain of protein sequences in crops plants known to be symbiotically related to N-fixing bacteria, undomesticated plants, and animals. The mean, SD, and the sample size (number of amino acids and proteins) for each species are shown on the right.