Rs26-Confetti as a tool to study megakaryocytes in vivo. (A) Rs26-Confetti gene product and Cre-dependent recombination; (B) representative endogenous Confetti fluorescence (YFP, RFP, GFP and CFP) and Gp1b (AlexaFluor647) staining of a bone marrow whole mount. *Indicates pro-platelet formation; (C and D) size and shape analysis of megakaryocytes (MK) in bone marrow whole mounts, n=93 cells in 8 bones; (E) representative MK expressing 1-4 colors; (F) percentage of MK expressing 1,2,3 or 4 colors, n=8 bones, ANOVA across color expression groups; (G to H) MK size related to color expression (1, 2, 3, 4 colors), n=93 cells in 8 bones; (G) ANOVA across color expression groups; (H) correlation analysis using linear regression. YFP: yellow fluorescent protein; GFP: green fluorescent protein; RFP: red green fluorescent protein; CFP: cyan green fluorescent protein.