An important part of the RNA components of the transcriptional regulatory network is the so-called, microRNAs (miRNAs), 20-22nt single stranded non-coding RNAs that act mainly as posttranscriptional repressors. They have been shown to control the transcriptional networks by acting on multiple targets and regulating the protein dosage of entire signaling pathways and have been implicated in many diseases. Recently, long non-coding RNAs (lncRNA) and circular RNAs (circRNAs) have also been described to regulate gene expression in different ways
In our laboratory we study the contribution of non-coding RNAs, including microRNAs, to the regulation of endothelial cell and macrophage functions. Both cell types play major role in controlling both angiogenic and inflammatory responses and the interplay between these two cell types has been shown to be critical for several pathophysiological conditions like atherosclerosis, cancer (tumor growth), adipose tissue expansion and wound healing, among others. Intriguingly, miRNAs can be transferred from cell to cell by exosomes, small vesicles that have been shown to mediate the transfer of proteins and RNAs, thus facilitating the exchange of information among cells this might have important implications in autocrine and paracrine communication between both macrophages and endothelial cells. This is an area of research that we are also investigating in our laboratory.
To this end, we are utilizing different approaches combining molecular and cellular biology, biochemistry, together with genetically modified mouse models.
Three main projects are currently ongoing:
1) Contribution of microRNAs to the regulation of endothelial cell functions. Our major focus involves studying the role of VEGF and TNF-regulated microRNAs on endothelial cell responses, as well as the identification of the molecular mechanisms whereby these cytokines regulate the biogenesis and activity of endothelial microRNAs.
2) To characterize novel regulatory mechanisms for macrophage activation and function.
3) Identification and characterization of regulatory RNAs species in exosomes derived form different set of activated macrophages, as well as their contribution to the regulation of endothelial cell functions in different pathophysiological conditions.