{"type": "root", "children": [{"type": "p", "children": [{"type": "t", "text": "\nMyo9b functions as a unique “motorized” Rho GTPase‐activating protein that couples an actin‐based motor domain with Rho inhibitory activity. In immune cells such as macrophages and cells undergoing active actin polymerization, Myo9b is recruited to dynamic structures—lamellipodia, ruffles, filopodia—where it spatially coordinates Rho activity to support proper cell spreading, polarization, and chemotaxis. Its targeted motor function ensures that localized Rho inhibition balances cellular protrusion and retraction, facilitating directional motility and effective immune surveillance."}, {"type": "fg", "children": [{"type": "fg_f", "ref": "1"}]}, {"type": "t", "text": ""}]}, {"type": "t", "text": "\n\n"}, {"type": "p", "children": [{"type": "t", "text": "\nBeyond its role in basic cell motility, Myo9b modulates diverse cellular functions that impact immune responses and tissue integrity. In dendritic cells and T lymphocytes, Myo9b regulates Rho signaling to control acto‐myosin contractility, which is essential for directed migration, basement membrane transmigration, and subsequent T cell priming and polarization. Alterations in Myo9b levels affect actin dynamics in osteogenic cells, thereby modulating spreading responses to growth factors such as IGF-1 and influencing bone formation. Additionally, in the context of autoimmune and inflammatory diseases as well as cancer metastasis, Myo9b deficiency has been linked to changes in T helper cell differentiation (shifting TH1/TH17 balance), delayed leukocyte infiltration, and diminished pleural tumor cell migration."}, {"type": "fg", "children": [{"type": "fg_fs", "start_ref": "3", "end_ref": "7"}]}, {"type": "t", "text": ""}]}, {"type": "t", "text": "\n\n"}, {"type": "p", "children": [{"type": "t", "text": "\nIn developmental and disease contexts, Myo9b’s role extends to orchestrating morphogenetic events and maintaining tissue homeostasis. Disruptions in its function are implicated in developmental anomalies such as abnormal lens formation during eye development and possibly contribute to neuromuscular disorders like Charcot-Marie-Tooth disease. 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