Abstract:
Based on the yeast′s nucleosome positions with single-base-pair accuracy, nucleosome core sequences and linker sequences extracted were used to discuss their fine structures and preferred motifs. Analyzing relative deviations (RD) of 3-mer relative frequency between core/linker sequences and genome-wide found that rare motifs (GCG, CGC, CGG and CCG) were the most important factor to distinguish two kinds of sequences, and the most abundant motifs (AAA and TTT) closely followed. After core sequences equally divided into three units, the RD distribution of the central unit was similar to that of core sequences, and the RD distributions of the flanking units were partially similar to that of linker sequences, which showed the flanking units have transition regions toward linker sequences.Based on the analysis of G+C contents in 11 groups with different length， it was found that the length was negatively correlated with the G+C content，while four main types of conserved motifs were found in these groups through search of MEME suite，indicating that linker sequence possesses diversity.
