Figure 3

Evolution of vertebrate lysozyme g sequences. Schematic model of the key evolutionary events in the evolution of vertebrate lysozyme g genes. Phylogeny of representative lysozyme g sequences is based on Figure 2. Gene duplication events, indicated by diamonds, which occurred in the amniote ancestor, on the early mammalian lineage, and an early teleost lineage are labeled A, M, and F, respectively. Large Xs refer to gene loss on the mammalian lineage after the gene duplications in the amniote ancestor. Loss of the signal peptide is indicated by “Δ signal peptide” and the loss of muramidase activity by “Δ activity”. Loss of the signal peptide in fish is associated with the gain of alternative splicing in these species.