Fig. 2

RPS6 is a universal marker of sex identity in avian fibroblast cells. A Genomic view of RPS6 in all studied species. This gene has single sharp TSS peak, one annotated isoform, and similar sizes in all species. Promoter sequences (500 bp) were analyzed for presence of estrogen hormone receptor DNA binding motifs. Motif matches with p value < 0.001 are shown. B A phylogenetic tree for RPS6 based on nucleotide sequences alignment. C CAGE expression profiles of RPS6 gene. Expression of RPS6 is higher in male fibroblast cells. FDR values from differential expression analysis are shown. Bottom right numbers represent fold change between male and female samples. D qPCR for RPS6 confirmed statistically stable up-regulation of the gene in male fibroblast cells. Number of biological replicates for chicken—3 males, 4 females (× 2 technical replicates). For other species, number of replicates is same in CAGE experimental design