Fig. 1
Evolutionary integration of NLSs in the annotated domains of eukaryotic and prokaryotic proteins. a Distribution of NLSs according to their localization in protein sequences relative to annotated protein domains. b IC distributions of NLSs that overlap with either nucleotide-binding domains, domains involved in protein-protein interactions or out-of-domain regions. The shift of distributions of NLSs overlapping with nucleotide-binding domains and domains involved in protein-protein interactions toward higher values of IC suggests that in-domain NLSs are more conservative relative to out-of-domain regions (one-way ANOVA test, p < 0.05, followed by the Bonferroni correction for multiple comparisons) c Distribution of the ratio of IC of the surrounding NLS region to that of the NLS. d Localization of prokaryotic proteins expressed as EGFP fusions in living HeLa cells. e Estimation of nuclear accumulation (Fnuc/Fcyt) of prokaryotic proteins fused to EGFP. The results are presented as the mean ± s.d. (n > 20). Proteins with an Fnuc/Fcyt ≤ 1.16 were classified as non-accumulated inside nuclei (gray bars); those with an Fnuc/Fcyt > 1.16 were classified as accumulated inside nuclei (colored bars). f Estimation of the nuclear accumulation of different prokaryotic proteins for which the presence of NLS(s) was not predicted using cNLS Mapper software (mean ± s.d.) (n > 20). g Estimation of the nuclear accumulation of EGFP fused to predicted NLSs from different prokaryotic proteins (mean ± s.d.) (n > 20). h Mutations in predicted NLSs influence the nuclear accumulation (Fnuc/Fcyt) of prokaryotic proteins. Each value represents the mean ± s.d. (n > 20). single asterisk: p < 0.05, double asterisk: p < 0.0001, Mann-Whitney test