Document Type
Article
Publication Date
4-27-2021
Abstract
Extracellular vesicles (EVs) are cell‐derived membrane vesicles that are released into the extracellular space. EVs encapsulate key proteins and mediate intercellular signalling pathways. Recently, primary cilia have been shown to release EVs under fluid‐shear flow, but many proteins encapsulated in these vesicles have never been identified. Primary cilia are ubiquitous mechanosensory organelles that protrude from the apical surface of almost all human cells. Primary cilia also serve as compartments for signalling pathways, and their defects have been associated with a wide range of human genetic diseases called ciliopathies. To better understand the mechanism of ciliopathies, it is imperative to know the distinctive protein profiles of the differently sourced EVs (cilia vs cytosol). Here, we isolated EVs from ciliated wild‐type (WT) and non‐ciliated IFT88 knockout (KO) mouse endothelial cells using fluid‐shear flow followed by a conventional method of EV isolation. EVs isolated from WT and KO exhibited distinctive sizes. Differences in EV protein contents were studied using liquid chromatography with tandem mass spectrometry (LC‐MS‐MS) and proteomic comparative analysis, which allowed us to classify proteins between ciliary EVs and cytosolic EVs derived from WT and KO, respectively. A total of 79 proteins were exclusively expressed in WT EVs, 145 solely in KO EVs, and 524 in both EVs. Our bioinformatics analyses revealed 29% distinct protein classes and 75% distinct signalling pathways between WT and KO EVs. Based on our statistical analyses and in vitro studies, we identified NADPH‐cytochrome P450 reductase (POR), and CD166 antigen (CD166) as potential biomarkers for ciliary and cytosolic EVs, respectively. Our protein‐protein interaction network analysis revealed that POR, but not CD166, interacted with either established or strong ciliopathy gene candidates. This report shows the unique differences between EVs secreted from cilia and the cytosol. These results will be important in advancing our understanding of human genetic diseases.
Recommended Citation
Mohieldin AM, Pala R, Beuttler R, Moresco JJ, Yates JR 3rd, Nauli SM. Ciliary extracellular vesicles are distinct from the cytosolic extracellular vesicles. J Extracell Vesicles. 2021;10(6):e12086. https://doi.org/10.1002/jev2.12086
Copyright
The authors
Creative Commons License
This work is licensed under a Creative Commons Attribution 4.0 License.
Included in
Amino Acids, Peptides, and Proteins Commons, Biological Phenomena, Cell Phenomena, and Immunity Commons, Cell Biology Commons, Genetic Phenomena Commons, Genetic Processes Commons, Medical Cell Biology Commons, Medical Genetics Commons, Medicinal and Pharmaceutical Chemistry Commons, Other Pharmacy and Pharmaceutical Sciences Commons, Pharmaceutical Preparations Commons
Comments
This article was originally published in Journal of Extracellular Vesicles, volume 10, issue 6, in 2021. https://doi.org/10.1002/jev2.12086