Figure 3

Ubiquitin and proteasome localization in early embryos. Chain linkage specific anti-ubiquitin antibodies and an antibody to a subunit of the 19S proteasome were used to stain embryos (red). The embryos were also stained with the 1CB4 antibody which recognizes the MO organelles from sperm (green). DAPI was used to visualize the DNA (blue). All embryos are oriented with anterior end at the right. The whole embryo is shown as well at an enlargement of the area of the MOs. MOs are initially found clustered around the sperm DNA (meiosis I and II). However, during mitosis, they disperse to random positions in the cytoplasm. All three antibodies (K48, K63 and proteasome) colocalize with MOs in meiotic embryos. However, only K63 continues to colocalize during mitosis and later (middle column).