Small interfering RNA knockdown of mini-TyrRS and mini-TrpRS effects angiogenesis in human umbilical vein endothelial cells in hypoxic culture

Abstract

Aim We studied the role of mini-TyrRS and mini-TrpRS in angiogenesis by using small interfering RNA-mediated mini-TyrRS/mini-TrpRS knockout in hypoxic culture of human umbilical vein endothelial cells. Methods SiRNA was used as the main method to inhibited the gene function. Silencing efficiency was assayed by real-time reverse transcription-polymerase chain reaction and western blotting. The angiogenic activity in vitro was evaluated by transwell migration assay and Matrigel-induced capillary tube formation in hypoxic culture. Cell proliferation was determined by crystal violet staining. Results The results showed that levels of the miniTyrRS/mini-TrpRS gene and protein in mock transfection group and negative control group were higher, but noticeably decreased in experimental group. However, no significant difference was detected between mock transfection group and negative control group, but there was a statistically significant difference compared with experimental group. For miniTyrRS-siRNA group, the cell migration, tube formation and the rate of cell proliferation were respectively inhibited by (47.4, 56.3, 65.4, 73.7%), (60.5, 69.1, 75.9, 83.6%) and (40.4, 56.2, 61.2, 68.0%). For miniTrpRS-siRNA, were respectively increased by (18.0, 33.8, 45.1, 56.4%), (18.3, 31.2, 40.3, 45.7%) and (8.4, 26.4, 38.2, 46.6%). Conclusion These results indicated that angiogenesis is either stimulated by mini-TyrRS or inhibited by mini-TrpRS in matrigel models in hypoxic culture, raising the possibility that mini-TyrRS stimulates a common downstream signaling event. Thus, naturally occurring fragments of two proteins involved in translation, TyrRS and TrpRS, have opposing activity on endothelial cell angiogenesis in the matrigel assays. The opposing activities of the two tRNA synthetases suggest tight regulation of the balance between pro-and anti-angiogenic stimuli.

Effect of Mini‐Tyrosyl‐tRNA Synthetase/Mini‐Tryptophanyl‐tRNA Synthetase on Angiogenesis in Rhesus Monkeys after Acute Myocardial Infarction

“…In our previous experiment [14][15][16][17][18], we have already indicated that the PI3-kinase/Akt and Erk pathway are two of the downstream substrates of the signal pathways. Moreover, it was demonstrated that the inhibitor of the PI3-kinase and Erk almost completely inhibited the proliferation and migration of mini-TyrRS/mini-TrpRS-induced rat coronary venular endothelial cells (RCVECs), which was consistent with the concept that the PI3-kinase/Akt and Erk pathways may mediate the angiogenic effects of mini-TyrRS/mini-TrpRS.…”

“…In our previous researches [14][15][16][17][18], we determined that miniTyrRS/mini-TrpRS proteins affected the proliferation and migration of rat coronary venular endothelial cells (RCVECs) in ischemic tissues. Angiogenesis is either stimulated by mini-TyrRS or inhibited by mini-TrpRS in rat myocardial infarction models, raising the possibility that mini-TyrRS/mini-TrpRS stimulates a common downstream signaling event.…”