Figure 4. The effect of P58^IPK on gene expression of ATF4, C/EBP homologous protein, GRP78 and vascular endothelial growth factor on human retinal capillary endothelial cells by western blot. A: Evaluation the effect of P58^IPK on gene expression of ATF4 on human retinal capillary endothelial cells (HRCECs) treated with tunicamycin by western blot: Group 1 is normal control that was not ER-stressed. Group 2 is HRCECs treated with tunicamycin. Group 3 is HRCECs transfected with rAAV2-P58^IPK and treated with tunicamycin. Group 4 is HRCECs transfected with pGIPZ-P58^IPK RNAi and treated with tunicamycin. The expression level of ATF4 in either group was: 0.12±0.03, 0.25±0.03, 0.16±0.04, and 0.33±0.04 (p< 0.001), respectively. B: Evaluation the effect of P58^IPK on gene expression of GRP78 on HRCECs treated with tunicamycin by western blot: Group 1:normal control that was not endothelial reticulum (ER)-stressed. Group 2 is HRCECs treated with tunicamycin. Group 3 is HRCECs transfected with rAAV2-P58^IPK and treated with tunicamycin. Group 4 is HRCECs transfected with pGIPZ-P58^IPK RNAi and treated with tunicamycin. The expression level of GRP78 in either group was: 0.10±0.02, 0.22±0.02, 0.12±0.03, and 0.17±0.02 (p< 0.001), respectively. C: Evaluation the effect of P58^IPK on gene expression of C/EBP homologous protein (CHOP) on HRCECs treated with tunicamycin by western blot: Group 1 is normal control that was not ER-stressed. Group 2 is HRCECs treated with tunicamycin. Group 3 is HRCECs transfected with rAAV2-P58^IPK and treated with tunicamycin. Group 4 is HRCECs transfected with pGIPZ-P58^IPK RNAi and treated with tunicamycin. The expression level of CHOP in either group was: 0.08±0.02, 0.18± 0.04, 0.10 ±0.03, and 0.26±0.03 (p< 0.001), respectively. D: Evaluation the effect of P58^IPK on gene expression of vascular endothelial growth factor (VEGF) on HRCECs treated with tunicamycin by western blot: Group 1 is normal control that was not ER-stressed. Group 2 is HRCECs treated with tunicamycin. Group 3 is HRCECs transfected with rAAV2-P58^IPK and treated with tunicamycin. Group 4 is HRCECs transfected with pGIPZ-P58^IPK RNAi and treated with tunicamycin. The expression level of VEGF in either group was: 0.06±0.01, 0.13±0.02, 0.08±0.01, and 0.17±0.02 (p< 0.001), respectively.