Macrophage nitric oxide synthase associates with cortical actin but is not recruited to phagosomes.

ABSTRACT: Nitric oxide (NO) produced from inducible NO synthase (iNOS) is an important component of host defense against intracellular pathogens. To understand how phagocytes deliver NO to ingested microorganisms while avoiding cytotoxicity, we set out to study the subcellular localization of iNOS within macrophages following phagocytosis. Confocal microscopy of immunostained cells showed that iNOS was located not only diffusely within cytoplasm but also in vesicles, as well as immediately adjacent to the peripheral cell membrane. This peripheral iNOS colocalized with the cortical actin cytoskeleton and was removed by the actin-depolymerizing drug cytochalasin B. Biochemical fractionation of RAW 264 macrophages showed that 32.75% (+/-5.11%; n = 3) of iNOS was present in a particulate fraction, which

SUBMITTER: Webb JL 

PROVIDER: S-EPMC98774 | biostudies-literature | 2001 Oct

REPOSITORIES: biostudies-literature