Fig. 3.
Effect of hypoxia on transcriptional activity of TGF-β2 gene in HUVECs.
Transcriptional analysis of TGF-β2, Glut-1, and GAPDH genes by nuclear run-on assay; 1 of 2 representative experiments is shown. (A) 5 μg of each of the plasmids indicated on the right bound to nylon membrane were hybridized with [32P]-labeled run-on transcripts from 6 × 109 nuclei isolated from HUVECs cultured for 24 hours in normoxia (20% O2) or hypoxia (1% O2). pUC19, the plasmid vector without insert, was used to estimate the background level. Radioactive bands were detected by autoradiography and also by PhosphorImager, from which transcripts were quantitated. (B) Fold increase in transcript levels in hypoxic HUVECs compared with normoxic controls was done by dividing the TGF-β2/GAPDH signal from hypoxic HUVECs by the TGF-β2/GAPDH signal obtained from normoxic HUVECs, which is shown as 1. The mean of results from 2 independent experiments is shown.