Fig. 3.
CRPE65 overexpression followed by lutein treatment gives rise to meso-zeaxanthin in HEK293T cells. Nontransfected HEK293T cells do not express RPE65, but transient transfection results in expression of this gene for several days (A). Treatment of CRPE65-transfected cells with 4 μM lutein resulted in meso-zeaxanthin production (C), whereas the cells overexpressing control plasmid were devoid of meso-zeaxanthin (B). The ratio of meso-zeaxanthin to lutein shows an increase in the latter in a time-dependent manner (D). Treatment with 4 μM zeaxanthin in control plasmid-overexpressing cells (E) or CRPE65-overexpressing cells did not result in meso-zeaxanthin production (F). n = 3. Error bars represent SEM. **P < 0.005; ***P < 0.0005.