cloned mouse Atg16l1, which encodes a deduced 623-amino acid protein with an N-terminal coiled-coil region and 7 WD repeats. They also identified 2 Atg16l1 isoforms with different sequences between the coiled-coil region and WD repeats. The N-terminal region of Atg16l1 shares weak but significant homology with S. cerevisiae Apg16, but the C-terminal region is absent from the S. cerevisiae protein. By database analysis, Mizushima et al. (2003) identified a human ATG16L1 transcript encoding a deduced 588-amino acid protein that corresponds to the shortest mouse isoform. Western blot analysis of mouse tissues detected a major 63-kD Atg16l1 protein and a minor 71-kD protein in liver, kidney, spleen, thymus, testis, and embryonic stem cells, and a 75-kD protein in brain, skeletal muscle, and heart.