RHOA-mediated mechanical force generation through Dectin-1.

ABSTRACT: Dendritic cell-associated C-type lectin 1 (Dectin-1, also known as CLEC7A) is an innate immune pattern recognition receptor that recognizes ?-glucan on the Candida albicans cell wall. Recognition of ?-glucan by immune cells leads to phagocytosis, oxidative burst, cytokine and chemokine production. We looked for specific mechanisms that coordinate phagocytosis downstream of Dectin-1 leading to actin reorganization and internalization of fungus. We found that stimulation of Dectin-1 by soluble ?-glucan leads to mechanical force generation and areal contraction in Dectin-1-transfected HEK-293 cells and M1 macrophages. With inhibitor studies, we found this force generation is a spleen tyrosine kinase (SYK)-independent, but SRC family kinase (SFK)-dependent process mediated through the RHOA-ROCK-myosin light chain (MLC) pathway. We confirmed activation of RHOA downstream of Dectin-1 using activity assays and stress fiber formation. Through phagocytosis assays, we found direct evidence for the importance of RHOA-ROCK-MLC signaling in the process of phagocytosis of C. albicans.

SUBMITTER: Choraghe RP 

PROVIDER: S-EPMC7063837 | biostudies-literature | 2020 Mar

REPOSITORIES: biostudies-literature