Figure 7
From: Neofunctionalization of a duplicate hatching enzyme gene during the evolution of teleost fishes
Cross-species digestion experiment exchanging hatching enzyme-egg envelope combinations between milkfish and medaka. Schematic diagrams of the cleavage sites of milkfish (A) and medaka hatching enzymes (B) on the egg envelope proteins, ZPB and ZPC. Black and gray arrowheads indicate cleavage sites of clade I and clade II enzyme, respectively. (C) The structural changes in the milkfish egg envelope caused by medaka hatching enzymes. The intact egg envelope, the MHCE-treated egg envelope, and the MLCE-treated egg envelope are shown from left to right. (D) The structural changes in the medaka egg envelope caused by medaka and milkfish hatching enzymes. The intact egg envelope, MHCE-treated egg envelope, MLCE-treated MHCE-swollen egg envelope are shown in the upper photos. The MfHE1-treated egg envelope, MfHE3-treated egg envelope, and MfHE3-treated MHCE-swollen egg envelope are shown in the lower photos. (E) SDS-PAGE patterns of the digests of milkfish egg envelope. Undigested fertilized egg envelope (lane 1), egg envelope digested by MHCE (lane 2), by MLCE (lane 3), by MfHE1 (lane 4), and by MfHE3 (lane 5). (F) SDS-PAGE of the digests of medaka egg envelope. Undigested fertilized egg envelope (lane 6), egg envelope digested by MHCE (lane 7) and MfHE1 (lane 9), MHCE-swollen egg envelope digested by MLCE (lane 8) and by MfHE3 (lane 10). The asterisk indicates the 15 and 16 kDa products produced by cleavage of the mid-ZPd site. Numbers on the left represent the sizes of molecular markers.