Fig. 5.

β-Tectorin with the ZP3 cytoplasmic tail is incorporated into the zona pellucida. (A) β-Tectorin (329 aa) has a signal peptide, a ‘zona’ domain, a potential dibasic cleavage site followed by a GPI-anchor site and a hydrophobic tail that is removed in the mature protein. β-Tectorin^Venus cDNA was modified by replacing its C-terminus with that of ZP3 and cloned into the expression vector β-tectorin–(ZP3 tail). (B) Lysates from CHO cells transfected with normal (Tectorin) and modified (Tec-ZP3) β-tectorin^Venus were assayed by immunoblot using monoclonal antibody against GFP that recognizes Venus. (C) Oocytes were co-injected with β-tectorin^Venus and ZP3^Cherry before imaging oocytes and zona ‘ghosts’ by confocal microscopy. Scale bar: 20 μm. (D) C-terminus of β-tectorin^Venus was replaced by that of ZP3 containing its cytoplasmic tail. Photomicrographs are representative images from experiments that were repeated three times with 10–20 oocytes.