Hemostasis and thrombus formation are impaired in V2^Δ3^Δ8^−/−animals. (A) Tail bleeding times were measured after tail transection of WT (n = 28), V3^−/− (n = 38), V2^Δ3^Δ (n = 20), V8^+/− (n = 26), V8^−/− (n = 31), V2^Δ3^Δ8^+/− (n = 41), and V2^Δ3^Δ8^−/− (n = 34) mice. (B) Thrombus formation in the carotid artery was induced by topical application of 5% FeCl₃, and blood flow was monitored in WT (n = 6), V8^+/− (n = 6), V2^Δ3^Δ (n = 7), V2^Δ3^Δ8^+/− (n = 9), V8^−/− (n = 7), and V2^Δ3^Δ8^−/− (n = 7) mice. For panels A and B, data are mean ± standard error of the mean. The P values (log-rank test) are indicated and ***P < .001. The red line indicates the mean, and the black line indicates the median. The box represents 25th-75th percentiles. Whiskers/error bars above and below the box indicate the 90th and 10th percentiles, respectively. Outliers are as shown in tail bleeding figure. (C) APTT and PT were measured in platelet-poor plasma prepared from WT (n = 7), V8^−/− (n = 5), V2^Δ3^Δ (n = 8), V2^Δ3^Δ8^+/− (n = 3), and V2^Δ3^Δ8^−/− (n = 5) mice. (D) PS exposure on the surface of thrombin-stimulated platelets from WT, V8^+/−, V8^−/−, V2^Δ3^Δ, V2^Δ3^Δ8^+/−, and V2^Δ3^Δ8^−/− mice was measured by fluorescein isothiocyanate–lactadherin binding and flow cytometry. The data are representative of 2 independent assays. *P < .05, Student t test. (E) A representative western blot showing the levels of TMEM16F in the indicated strains. Rab GDI was used as a loading control.