RHOA-mediated mechanical force generation through Dectin-1

Authors

Rohan P. Choraghe, Department of Pathology, University of New Mexico, Albuquerque, NM 87131, USA
Tomasz Kołodziej, Department of Pathology, University of New Mexico, Albuquerque, NM 87131, USA
Alan Buser, Department of Pathology, University of New Mexico, Albuquerque, NM 87131, USA
Zenon Rajfur, Institute of Physics, Jagiellonian University, Krakow 30-348, Poland
Aaron K. Neumann, Department of Pathology, University of New Mexico, Albuquerque, NM 87131, USA akneumann@salud.unm.edu

Document Type

Article

Publication Date

3-2-2020

Abstract

Dendritic cell-associated C-type lectin 1 (Dectin-1, also known as CLEC7A) is an innate immune pattern recognition receptor that recognizes β-glucan on the Candida albicans cell wall. Recognition of β-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 β-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.

Recommended Citation

Choraghe RP, Kołodziej T, Buser A, Rajfur Z, Neumann AK. RHOA-mediated mechanical force generation through Dectin-1. J Cell Sci. 2020 Mar 2;133(5):jcs236166. doi: 10.1242/jcs.236166. PMID: 31964711; PMCID: PMC7063837.