Figure 2

Levels of conserved synteny between green algae. (a) Dot-plot of 5,232 putative orthologous genes in the genome assemblies of C-169 and C. variabilis. Red and green dots show orthologous genes on the same and opposite strands, respectively. The width and length of each box are proportional to the lengths (bp) of the scaffolds determining the box. Scaffolds are organized in decreasing size order. The background color of boxes reflects the statistical significance (Z-score) of the number of orthologous genes (that is, conservation of synteny) shared between pairs of scaffolds relative to a non-syntenic model. The figure shows only the 29 biggest scaffolds of each species. (b) Numbers of conserved adjacent gene pairs and synteny correlation coefficients between pairs of sequenced chlorophytes appearing in the phylogenetic tree shown on the left. The maximum likelihood phylogenetic tree of sequenced chlorophytes was computed with the WAG+G+I model from a concatenated alignment of 1,253 orthologous proteins totaling 263,131 gap-free sites. The upper half of the matrix shows the levels of synteny conservation between pairs of genome assemblies as measured by the synteny correlation coefficient [17]. The lower half shows the numbers of pairs of orthologous genes that are adjacent in two genome assemblies. The background color of boxes reflects the statistical significance (Z-score) of the synteny correlation coefficient (blue) and number of conserved adjacent gene pairs (orange) relative to a non-syntenic model. Olu, Ostreococcus lucimarinus; ORCC, Ostreococcus sp. RCC809; Ota, Ostreococcus tauri; MRCC, Micromonas sp. RCC299; MCCMP, Micromonas pusilla CCMP1545; Crei, Chlamydomonas reinhardtii; Vcar, Volvox carteri; Chlo, Chlorella variabilis NC64A; Cocco, Coccomyxa subellipsoidea C-169.