Fig. 1.

Composition of the human testis phosphoproteome and proteome. A,, Venn diagram showing the number of phosphopeptides (based on spectral counting) identified by TiO₂-based phosphoproteomics in the three human testicular tissue samples from donors with full spermatogenesis included in this study. B,, Total number of phosphoproteins identified from the testicular phosphopeptide list and the overlap within biological replicates. C,, Compilation of proteins identified in the human testis by LC-MS/MS approaches. The total list of proteins identified in the present study was combined with the previous report from Liu et al., (52). D,, Proportion of phosphoproteins identified within the total human testicular proteome (present study and Liu et al.,, 2013(52)).