OBJECTIVE: This study aimed to examine (1) whether polarity protein partitioning defective-3 (PARD-3) was expressed in endothelial cells (ECs) and contributed to endothelial barrier integrity and (2) whether altered PARD-3 expression and distribution were associated with disturbed endothelial junction protein VE-cadherin expression induced by factors derived from preeclamptic (PE) placentas. METHODS: PARD-3 and VE-cadherin expressions were examined by immunofluorescent staining and Western blot in confluent ECs and in ECs treated with normal and PE placental conditioned medium (CM). Protein-protein interactions between PARD-3/VE-cadherin, PARD-3/ atypical protein kinase C (aPKCλ), and VE-cadherin/aPKCλ were examined by immuno-precipitation and immunobloting. RESULTS: Similar to VE-cadherin, PARD-3 is localized at the cell contacts in control ECs. Both PARD-3 and VE-cadherin expressions were markedly reduced in cells treated with PE-CM for 2h, but not in cells treated with normal-CM compared to non-treated controls. Cytosol staining of VE-cadherin and PARD-3 was pronounced in cells after 24h treatment with PE-CM. PARD-3/VE-cadherin and PARD-3/aPKCλ complexes were detected in PE-CM treated cells, but not in untreated control cells and in cells after recovery. In contrast, VE-cadherin/aPKCλ complex was detected in control cells and in cells after recovery, but not in PE-CM treated cells. CONCLUSIONS: Polarity protein PARD-3 is localized at cell contacts. Factors-derived from PE placentas not only interrupt junction protein VE-cadherin distribution, but also perturb polarity protein PARD-3 expression and distribution in ECs. The results of PARD-3/VE-cadherin and PARD-3/aPKCλ complexes formation in cells treated with placental CM suggest that factors-derived from placenta could interfere both junction protein and polarity protein functions in ECs.
OBJECTIVE: This study aimed to examine (1) whether polarity protein partitioning defective-3 (PARD-3) was expressed in endothelial cells (ECs) and contributed to endothelial barrier integrity and (2) whether altered PARD-3 expression and distribution were associated with disturbed endothelial junction protein VE-cadherin expression induced by factors derived from preeclamptic (PE) placentas. METHODS:PARD-3 and VE-cadherin expressions were examined by immunofluorescent staining and Western blot in confluent ECs and in ECs treated with normal and PE placental conditioned medium (CM). Protein-protein interactions between PARD-3/VE-cadherin, PARD-3/ atypical protein kinase C (aPKCλ), and VE-cadherin/aPKCλ were examined by immuno-precipitation and immunobloting. RESULTS: Similar to VE-cadherin, PARD-3 is localized at the cell contacts in control ECs. Both PARD-3 and VE-cadherin expressions were markedly reduced in cells treated with PE-CM for 2h, but not in cells treated with normal-CM compared to non-treated controls. Cytosol staining of VE-cadherin and PARD-3 was pronounced in cells after 24h treatment with PE-CM. PARD-3/VE-cadherin and PARD-3/aPKCλ complexes were detected in PE-CM treated cells, but not in untreated control cells and in cells after recovery. In contrast, VE-cadherin/aPKCλ complex was detected in control cells and in cells after recovery, but not in PE-CM treated cells. CONCLUSIONS: Polarity protein PARD-3 is localized at cell contacts. Factors-derived from PE placentas not only interrupt junction protein VE-cadherin distribution, but also perturb polarity protein PARD-3 expression and distribution in ECs. The results of PARD-3/VE-cadherin and PARD-3/aPKCλ complexes formation in cells treated with placental CM suggest that factors-derived from placenta could interfere both junction protein and polarity protein functions in ECs.
Authors: Yuping Wang; David F Lewis; Yang Gu; Yanping Zhang; J Steve Alexander; D Neil Granger Journal: J Clin Endocrinol Metab Date: 2004-05 Impact factor: 5.958
Authors: A Suzuki; T Yamanaka; T Hirose; N Manabe; K Mizuno; M Shimizu; K Akimoto; Y Izumi; T Ohnishi; S Ohno Journal: J Cell Biol Date: 2001-03-19 Impact factor: 10.539