The SWELL1-LRRC8 complex regulates endothelial AKT-eNOS signaling and vascular function
- Washington University School of Medicine, United States
- Washington University, United States
- University of Iowa, United States
- Washington University in St. Louis, United States
Abstract
The endothelium responds to numerous chemical and mechanical factors in regulating vascular tone, blood pressure and blood flow. The endothelial volume regulatory anion channel (VRAC) has been proposed to be mechano-sensitive and thereby sense fluid flow and hydrostatic pressure to regulate vascular function. Here, we show that the Leucine Rich Repeat Containing Protein 8a, LRRC8A (SWELL1) is required for VRAC in human umbilical vein endothelial cells (HUVECs). Endothelial LRRC8A regulates AKT-eNOS signaling under basal, stretch and shear-flow stimulation, forms a GRB2-Cav1-eNOS signaling complex, and is required for endothelial cell alignment to laminar shear flow. Endothelium-restricted Lrrc8a KO mice develop hypertension in response to chronic angiotensin-II infusion and exhibit impaired retinal blood flow with both diffuse and focal blood vessel narrowing in the setting of Type 2 diabetes (T2D). These data demonstrate that LRRC8A regulates AKT-eNOS in endothelium and is required for maintaining vascular function, particularly in the setting of T2D.
Data availability
RNA sequencing data has been deposited in GEO under accession number GSE166989. All other data available as source data files.
-
The SWELL1-LRRC8 complex regulates endothelial AKT-eNOS- mTOR signaling and vascular functionNCBI Gene Expression Omnibus, GSE166989.
Article and author information
Author details
Funding
National Institute of Diabetes and Digestive and Kidney Diseases (R01DK106009)
- Rajan Sah
National Heart, Lung, and Blood Institute (5R00HL125683)
- Amber N Stratman
National Heart, Lung, and Blood Institute (R01 HL125436)
- Chad E Grueter
National Heart, Lung, and Blood Institute (R35 GM137976)
- Amber N Stratman
VA Merit Award (I01BX005072)
- Rajan Sah
King Abdullah International Medical Research Center (RA17-014-A)
- Ahmad F Alghanem
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Ethics
Animal experimentation: Animal experimentation: This study was performed in accordance with the recommendations in the Guide for the Care and Use of Laboratory Animals of the National Institutes of Health. All of the animals were handled according to the approved institutional animal care and use committee (IACUC) protocols of Washington University in St. Louis (20180217) and the University of Iowa (1308148).
Copyright
© 2021, Alghanem et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
Metrics
-
- 2,623
- views
-
- 382
- downloads
-
- 45
- citations
Views, downloads and citations are aggregated across all versions of this paper published by eLife.
Download links
A two-part list of links to download the article, or parts of the article, in various formats.
Downloads (link to download the article as PDF)
Open citations (links to open the citations from this article in various online reference manager services)
Cite this article (links to download the citations from this article in formats compatible with various reference manager tools)
The SWELL1-LRRC8 complex regulates endothelial AKT-eNOS signaling and vascular function
eLife 10:e61313.
https://doi.org/10.7554/eLife.61313
Further reading
-
- Cell Biology
Existence of cilia in the last eukaryotic common ancestor raises a fundamental question in biology: how the transcriptional regulation of ciliogenesis has evolved? One conceptual answer to this question is by an ancient transcription factor regulating ciliary gene expression in both uni- and multicellular organisms, but examples of such transcription factors in eukaryotes are lacking. Previously, we showed that an ancient transcription factor X chromosome-associated protein 5 (Xap5) is required for flagellar assembly in Chlamydomonas. Here, we show that Xap5 and Xap5-like (Xap5l) are two conserved pairs of antagonistic transcription regulators that control ciliary transcriptional programs during spermatogenesis. Male mice lacking either Xap5 or Xap5l display infertility, as a result of meiotic prophase arrest and sperm flagella malformation, respectively. Mechanistically, Xap5 positively regulates the ciliary gene expression by activating the key regulators including Foxj1 and Rfx families during the early stage of spermatogenesis. In contrast, Xap5l negatively regulates the expression of ciliary genes via repressing these ciliary transcription factors during the spermiogenesis stage. Our results provide new insights into the mechanisms by which temporal and spatial transcription regulators are coordinated to control ciliary transcriptional programs during spermatogenesis.
-
- Cell Biology
Chemokine receptors are GPCRs that regulate the chemotactic migration of a wide variety of cells including immune and cancer cells. Most chemokine receptors contain features associated with the ability to stimulate G protein signaling during β-arrestin-mediated receptor internalization into endosomes. As endosomal signaling of certain non-GPCR receptors plays a major role in cell migration, we chose to investigate the potential role of endosomal chemokine receptor signaling on mechanisms governing this function. Applying a combination of pharmacological and cell biological approaches, we demonstrate that the model chemokine receptor CCR7 recruits G protein and β-arrestin simultaneously upon chemokine stimulation, which enables internalized receptors to activate G protein from endosomes. Furthermore, spatiotemporal-resolved APEX2 proteome profiling shows that endosomal CCR7 uniquely enriches specific Rho GTPase regulators as compared to plasma membrane CCR7, which is directly associated with enhanced activity of the Rho GTPase Rac1 and chemotaxis of immune T cells. As Rac1 drives the formation of membrane protrusions during chemotaxis, our findings suggest an important integrated function of endosomal chemokine receptor signaling in cell migration.
