Genomic signals for whole chromosomes

摘要

The paper presents results in the analysis of genomic information at the scale of whole chromosomes or whole genomes based on the conversion into genomic signals. Mainly, the phase analysis -- phase, cumulated phase and unwrapped phase, and the sequence path analysis are presented. The unwrapped phase displays an almost linear variation along whole chromosomes. The property holds for all the investigated genomes, being shared by both prokaryotes and eukaryotes, while the magnitude and sign of the unwrapped phase slope is specific for each taxon and chromosome. Such a behavior proves a rule similar to Chargaff s rule, but reveals a statistical regularity of the succession of the nucleotides - a second order statistics, not only of the distribution of nucleotides - a first order statistics. The cumulated phase of the genomic signal of certain prokaryotes also shows interesting specific behavior. The comparison between the behavior of the cumulated phase and of the unwrapped phase across the putative origins and termini of the replichores suggests an interesting model for the structure of chromosomes.