LAT is required for shedding but not for internalization/intracellular clearing of GPVI. Wild-type (•) or LAT^−/− (○) mice received 20 μg biotinylated JAQ1 intravenously and (A) platelet counts were determined. (B) Surface-bound JAQ1^biotin was detected by flow cytometric measurement of streptavidin^FITC binding and is given as percentage of maximal binding determined in vitro. (C) Detection of sGPVI/JAQ1^biotin complex in plasma at the indicated time points after antibody injection. (A-C) Results are expressed as the mean platelet count ± SD for groups of 6 mice each. (D) Western blot analysis of platelets at the indicated time points. The results are representative of 3 individual experiments.