Fig. 4: Fate of sex chromosomes during transitions from dioicy to co-sexuality (monoicy).
From: Origin and evolutionary trajectories of brown algal sex chromosomes
a, Comparison of the U/V-homologue in C. linearis against the U and V chromosomes of Ectocarpus sp. 7. b, Comparison of the U/V-homologue in D. dudresnayi against the U and V chromosomes of D. herbacea. The colour code represents the identity of the genes alongside the chromosomes, while the shapes represent the evolutionary fate of each SDR gene in the monoicous genome. The matching shades between the SDRs and the U/V-homologue are either colour coded by their ancestral background or they appear as transparent dotted shades if the gametologue of the other sex was retained. c, Karyoplot of D. dudresnayi showing the following features from bottom to top: chromosome compartment (autosomes and U/V-homologue), relative gene ages, interspecies Ks values, proportion of coding (CDS, red) and repeat (TEs, blue) density. Statistically significant differences for each feature between each autosome and the U/V-homologue are depicted on top of the track for that autosome (FDR-corrected two-sided Wilcoxon rank-sum test; values indicated with solid colours when P < 0.01 for the tested hypothesis). d, Violin plot showing the relative gene age ranks (higher ranks equate to younger ages) of the TRGs between the autosomes and the U/V-homologue of D. dudresnayi. Statistically significant difference in mean values of gene ages (centre line) was assessed using an FDR-corrected two-sided permutation test.
