Department of Biomedical Engineering, Oregon Health and Science University, Portland, United States; OHSU Center for Spatial Systems Biomedicine (OCSSB), Oregon Health and Science University, Portland, United States
Carey Phelps
Department of Biomedical Engineering, Oregon Health and Science University, Portland, United States; OHSU Center for Spatial Systems Biomedicine (OCSSB), Oregon Health and Science University, Portland, United States
Tao Huang
Department of Biomedical Engineering, Oregon Health and Science University, Portland, United States; OHSU Center for Spatial Systems Biomedicine (OCSSB), Oregon Health and Science University, Portland, United States
Department of Biomedical Engineering, Oregon Health and Science University, Portland, United States; OHSU Center for Spatial Systems Biomedicine (OCSSB), Oregon Health and Science University, Portland, United States
Lei Wu
Department of Biomedical Engineering, Oregon Health and Science University, Portland, United States; OHSU Center for Spatial Systems Biomedicine (OCSSB), Oregon Health and Science University, Portland, United States; Department of Oral Maxillofacial-Head Neck Oncology, School and Hospital of Stomatology, Wuhan University, Wuhan, China
Ying Zhang
Department of Biomedical Engineering, Oregon Health and Science University, Portland, United States; OHSU Center for Spatial Systems Biomedicine (OCSSB), Oregon Health and Science University, Portland, United States
Kai Tao
Department of Biomedical Engineering, Oregon Health and Science University, Portland, United States; OHSU Center for Spatial Systems Biomedicine (OCSSB), Oregon Health and Science University, Portland, United States
Young Hwan Chang
Department of Biomedical Engineering, Oregon Health and Science University, Portland, United States; OHSU Center for Spatial Systems Biomedicine (OCSSB), Oregon Health and Science University, Portland, United States
Philip JS Stork
Vollum Institute, Oregon Health and Science University, Portland, United States
Department of Biomedical Engineering, Oregon Health and Science University, Portland, United States; OHSU Center for Spatial Systems Biomedicine (OCSSB), Oregon Health and Science University, Portland, United States
Department of Biomedical Engineering, Oregon Health and Science University, Portland, United States; OHSU Center for Spatial Systems Biomedicine (OCSSB), Oregon Health and Science University, Portland, United States
Department of Biomedical Engineering, Oregon Health and Science University, Portland, United States; OHSU Center for Spatial Systems Biomedicine (OCSSB), Oregon Health and Science University, Portland, United States; Knight Cancer Early Detection Advanced Research (CEDAR) Center, Oregon Health and Science University, Portland, United States
Membrane nanodomains have been implicated in Ras signaling, but what these domains are and how they interact with Ras remain obscure. Here, using single particle tracking with photoactivated localization microscopy (spt-PALM) and detailed trajectory analysis, we show that distinct membrane domains dictate KRasG12D (an active KRas mutant) diffusion and trafficking in U2OS cells. KRasG12D exhibits an immobile state in ~70 nm domains, each embedded in a larger domain (~200 nm) that confers intermediate mobility, while the rest of the membrane supports fast diffusion. Moreover, KRasG12D is continuously removed from the membrane via the immobile state and replenished to the fast state, reminiscent of Ras internalization and recycling. Importantly, both the diffusion and trafficking properties of KRasG12D remain invariant over a broad range of protein expression levels. Our results reveal how membrane organization dictates membrane diffusion and trafficking of Ras and offer new insight into the spatial regulation of Ras signaling.
