RT Journal Article SR Electronic T1 Initial phospholipid-dependent Irgb6 targeting to Toxoplasma gondii vacuoles mediates host defense JF Life Science Alliance JO Life Sci. Alliance FD Life Science Alliance LLC SP e201900549 DO 10.26508/lsa.201900549 VO 3 IS 1 A1 Youngae Lee A1 Hiroshi Yamada A1 Ariel Pradipta A1 Ji Su Ma A1 Masaaki Okamoto A1 Hikaru Nagaoka A1 Eizo Takashima A1 Daron M Standley A1 Miwa Sasai A1 Kohji Takei A1 Masahiro Yamamoto YR 2020 UL https://www.life-science-alliance.org/content/3/1/e201900549.abstract AB Toxoplasma gondii is an obligate intracellular protozoan parasite capable of infecting warm-blooded animals by ingestion. The organism enters host cells and resides in the cytoplasm in a membrane-bound parasitophorous vacuole (PV). Inducing an interferon response enables IFN-γ–inducible immunity-related GTPase (IRG protein) to accumulate on the PV and to restrict parasite growth. However, little is known about the mechanisms by which IRG proteins recognize and destroy T. gondii PV. We characterized the role of IRG protein Irgb6 in the cell-autonomous response against T. gondii, which involves vacuole ubiquitination and breakdown. We show that Irgb6 is capable of binding a specific phospholipid on the PV membrane. Furthermore, the absence of Irgb6 causes reduced targeting of other effector IRG proteins to the PV. This suggests that Irgb6 has a role as a pioneer in the process by which multiple IRG proteins access the PV. Irgb6-deficient mice are highly susceptible to infection by a strain of T. gondii avirulent in wild-type mice.