|
Fig. 4 Figure 4. Loss of mouse Ythdc2 results in germ cells with a mixed mitotic/meiotic identity (A) Single-cell purification of 4n germ cells from mouse testes of Ythdc2+/− and Ythdc2−/− (KO) P10 animals. (B) UMAP-based integrated single-cell map of Ythdc2+/− and Ythdc2−/− (KO) testicular 4n germ cells (left). Annotated cell types are assigned a specific color. Genotype-separated single-cell maps are shown (right). Notice the presence of two unique cell populations present only in the KO testes. (C) Analysis of the indicated mitotic and meiotic marker genes expression. UMAP-based single-cell maps are ordered based on the developmental trajectory: mitotic spermatogonia (SG) marker expression (left), differentiating SG cell marker expression (middle), and leptotene/zygotene meiotic markers expression (right). Note that differentiating SG and meiotic markers are simultaneously expressed in the two populations of cells found exclusively in the Ythdc2 KO. See also Figures S4B and S4C. (D) Model showing how YTHDC2 acts during the mitotic-meiotic transition. In the absence of Ythdc2, germ cells display a mixed identity with expression of markers present in both differentiating SG and meiotic cells.