Human Immunological Diseases Section, Laboratory of Clinical Immunology and Microbiology, Division of Intramural Research (DIR), National Institute of Allergy and Infectious Diseases (NIAID), National Institutes of Health (NIH), Bethesda, MD, USA.
Citations 1
Germline mutations in a G protein identify signaling cross-talk in T cells
Science | September 19, 2024 | Volume: 385 | Issue: 6715 | Pages: No page available
Humans with monogenic inborn errors responsible for extreme disease phenotypes can reveal essential physiological pathways. We investigated germline mutations in GNAI2 , which encodes G αi2 , a key component in heterotrimeric G protein signal transduction usually thought to regulate adenylyl cyclase–mediated cyclic adenosine monophosphate (cAMP) production. Patients with activating G αi2 mutations had clinical presentations that included impaired immunity. Mutant G αi2 impaired cell migration and augmented responses to T cell receptor (TCR) stimulation. We found that mutant G αi2 influenced TCR signaling by sequestering the guanosine triphosphatase (GTPase)–activating protein RASA2, thereby promoting RAS activation and increasing downstream extracellular signal–regulated kinase (ERK)/mitogen-activated protein kinase (MAPK) and phosphatidylinositol 3-kinase (PI3K)–AKT S6 signaling to drive cellular growth and proliferation.