- "Revision_Shuttling modeling" folder includes computer codes for implementing the shuttling model in Figure 4A and "The mathematical model of BMP4-Chordin-Twsg1-BMP-1 circuit" section in supplementary Text using parameters in Table S4, as well as shuttling modeling figures used in Fig. 4C-E (left), Fig. S6 and Fig. S9 (left).
- "Constructs used in the study" folder includes the maps of constructs used in this manuscript listed in Table S2.
- "Revision_Shuttling data except for movies" folder includes all the raw imaging and flow cytometry data except for time-lapse movies. These data were processed by computer codes in the "Data Processing Codes" subfolders. The filenames and texts of computer codes link raw data with figures.
- Under "Revision_Shuttling movies" folder, the "Movie Analysis" subfolders have all the computer codes for processing the time-lapse imaging data, as well as stitched movie images and quantification. 
- Time-lapse imaging data were in "Revision_Shuttling movies" folder, but for uploading purposes, they are separately uploaded as "Gradient Movie Rep1.zip", "Gradient Movie Rep2.zip", "Gradient Movie Rep3.zip", "Gradient Movie Background.zip" and "rBMP4 Movie (MovieS2toS4).zip". Because of this change, you might need to change the directory paths of some movie analysis codes.