GSE109312
Effect of NFE2L2 silencing on miRNA profile of human aortic endothelial cells (HAECs) in response to GDF-15 and SDF-1
Nrf2 is a transcription factor playing an essential role in stress response. A knowledge of the significance of Nrf2 in cell function has not, as yet, reached out beyond transactivation of gene expression. This paper shows that GDF-15 and SDF-1-induced angiogenesis strongly depends on Nrf2 presence, but is not related to its transcriptional activity. We propose, that Nrf2 serves as a protein restraining Keap1, its known transcriptional repressor. Deficiency of Nrf2 protein available for Keap1 leads to overabundance of RhoGAP1, the protein regulating Cdc42 activity, and impairs podosome assembly, thereby indisposing actin rearrangements, and preventing angiogenesis. These activities can be rescued by concomitant deletion of RhoGAP1 or Keap1. We suggest that a new Nrf2 function of a Keap1 scavenger implies revising the established murine model of Nrf2 deficiency as a transcriptional knock out (tKO) mouse. The N-terminal fragment of Nrf2, containing Neh2 domain binding Keap1, is present in these animals. Thus, regarding the function of Nrf2 as a protein sequestering Keap1, both published and unpublished data on Nrf2-Keap1 duet may gain new interpretation. Overall design: miRNA profile of human aortic endothelial cells (HAECs) transfected with scrambled (siMock) or NFE2L2 (siNFE2L2) siRNA, stimulated with PBS, GDF-15 (250 ng/mL) or SDF-1 (100 ng/mL)