Fig. 6. A model for the cataract formation produced by 8-S50P mutation. Normal embryonic and postnatal lenses are formed in the presence of wild-type 8 (8-WT) and 3 (3-WT) connexins (following the black arrows). In the absence of 3-WT, the interaction between 8-S50P mutant connexin (8-S50P) and 8-WT suppresses the elongation of primary fiber cells in embryonic lenses but does not affect the formation of secondary fiber cells in postnatal lenses (following the red arrows). In the absence of 8-WT, the 8-S50P mutant connexin interacts with endogenous 3-WT to disrupt the formation of secondary fiber cells in postnatal lenses but does not affect the elongation of primary fiber cells (following the green arrows).