| First Author | Biswas S | Year | 2020 |
| Journal | Cells | Volume | 9 |
| Issue | 10 | PubMed ID | 33066124 |
| Mgi Jnum | J:309983 | Mgi Id | MGI:6705491 |
| Doi | 10.3390/cells9102280 | Citation | Biswas S, et al. (2020) IRAG1 Deficient Mice Develop PKG1beta Dependent Pulmonary Hypertension. Cells 9(10):2280 |
| abstractText | PKGs are serine/threonine kinases. PKG1 has two isoforms-PKG1alpha and beta. Inositol trisphosphate receptor (IP3R)-associated cGMP-kinase substrate 1 (IRAG1) is a substrate for PKG1beta. IRAG1 is also known to further interact with IP3RI, which mediates intracellular Ca(2+) release. However, the role of IRAG1 in PH is not known. Herein, WT and IRAG1 KO mice were kept under normoxic or hypoxic (10% O2) conditions for five weeks. Animals were evaluated for echocardiographic variables and went through right heart catheterization. Animals were further sacrificed to prepare lungs and right ventricular (RV) for immunostaining, western blotting, and pulmonary artery smooth muscle cell (PASMC) isolation. IRAG1 is expressed in PASMCs and downregulated under hypoxic conditions. Genetic deletion of IRAG1 leads to RV hypertrophy, increase in RV systolic pressure, and RV dysfunction in mice. Absence of IRAG1 in lung and RV have direct impacts on PKG1beta expression. Attenuated PKG1beta expression in IRAG1 KO mice further dysregulates other downstream candidates of PKG1beta in RV. IRAG1 KO mice develop PH spontaneously. Our results indicate that PKG1beta signaling via IRAG1 is essential for the homeostasis of PASMCs and RV. Disturbing this signaling complex by deleting IRAG1 can lead to RV dysfunction and development of PH in mice. |
