Generation of a hypoxia‐sensing mouse model

Abstract

Summary Oxygen (O2) homeostasis is essential to the metazoan life. O2‐sensing or hypoxia‐regulated molecular pathways are intimately involved in a wide range of critical cellular functions and cell survival from embryogenesis to adulthood. In this report, we have designed an innovative hypoxia sensor (O2CreER) based on the O2‐dependent degradation domain of the hypoxia‐inducible factor‐1α and Cre recombinase. We have further generated a hypoxia‐sensing mouse model, R26‐O2CreER, by targeted insertion of the O2CreER‐coding cassette in the ROSA26 locus. Using the ROSAmTmG mouse strain as a reporter, we have found that this novel hypoxia‐sensing mouse model can specifically identify hypoxic cells under the pathological condition of hind‐limb ischemia in adult mice. This model can also label embryonic cells including vibrissal follicle cells in E13.5–E15.5 embryos. This novel mouse model offers a valuable genetic tool for the study of hypoxia and O2 sensing in mammalian systems under both physiological and pathological conditions.

Pathogenic CD8 T cell responses are driven by neutrophil-mediated hypoxia in cutaneous leishmaniasis

“…C57BL/6 CD45.2 and CD45.1 mice (6 weeks old) were purchased from Charles River, and Prdm1 YFP (here called Blimp-1 reporter), ODD cre /ERT2 ( 63 ), Gzmb cre , Blimp-1 flox/flox , and RAG -/- (B6.12957-RAG1 tm1Mom ) were purchased from The Jackson Laboratory and crossed in our mouse facility. Cybb -/- mice ( 109 ) were obtained from Dr. Juhi Bagaitkar at Nationwide Children’s Hospital, Columbus, USA.…”

“…3b), suggesting a link between Blimp-1 and cytotoxicity. Finally, to assess if granzyme B expression in lesions resulted from hypoxic induction of Blimp-1, we used mice expressing a fusion protein bearing an oxygen-dependent degradation (ODD) domain from human HIF1A (hypoxia-inducible factor 1, alpha subunit) fused to a tamoxifen-inducible Cre recombinase gene (cre/ERT2) (63). When expressed under normoxic conditions, the O2CreER fusion protein is degraded rapidly but is stabilized by hypoxia when combined with tamoxifen injection.…”