APCDD1 and cyst: We therefore examined germline development by using Hts antibody (red in Figure 1—figure supplement 1) to reveal a rounded spectrosome, characteristic of single germline cells, or a branched fusome, which connects Vasa-marked germline cells (green in Figure 1—figure supplement 1) within a cyst (Deng and Lin, 1997), and by incubating samples with EdU to assess DNA replication as a proxy for cell division (Figure 1—figure supplement 2).