Skip to main content
. 2021 Feb 22;6(4):e134881. doi: 10.1172/jci.insight.134881

Figure 1. Overexpression of the β1 subunit increases expression of tight junction proteins.

Figure 1

(A) Rat primary ATII cells differentiate into ATI-like cells when cultured in vitro. Cells were lysed for qPCR analysis of ATII markers (SPC and LAMP3) and ATI markers (CAV1 and PDPN) at different days after culture. Data represents n = 3 biological replicates. (B) Relative mRNA levels for occludin and zo-1 in control and the β1 subunit–transfected cells. (C) Cells were transfected with plasmid expressing the rat β1 subunit or pCDNA3 empty plasmid as control at day 3 after isolation. Cells were lysed for Western blot 24 hours later. (D) Quantification of the Western blots in C. Data are representative of 3 independent experiments. Data are presented as mean ± SD. Statistical analysis was performed by 2-tailed Student’s t test. *P < 0.05; **P < 0.01; ***P < 0.001. (E) Ouabain treatment at the indicated concentrations does not inhibit the β1 subunit–mediated occludin upregulation. AT1 cells were transfected with the pCDNA3 plasmid or the pCMV-β1 plasmid, and 4 hours later, the DMSO control or ouabain at 10 nM, 100 nM, or 1 μM was added to cells. (F) Western blots were performed at 24 hours after transfection and were quantified. Data are representative of 3 independent experiments. Data are presented as mean ± SD. Statistical analysis was performed by 2-tailed Student’s t test. *P < 0.05; **P < 0.01.