Fig. 3. Sdf1 acts as a chemoattractant for cxcr4a-expressing endodermal cells. (A) Schematic representation of the cell-transplantation approach. nlacZ, sdf1a or sdf1b mRNA was co-injected with dextran-Alexa594 into WT donor zebrafish embryos at the one-cell stage. Donor cells from dome-stage embryos were placed in the ventrolateral margin of sdf1MOs-injected host embryos at the shield stage. (B-J) Lateral views of a Tg(sox17:EGFP) transgenic embryo with anterior to the top, at TB stage. V, ventral; D, dorsal. (B-D) nlacZ-expressing donor cells do not attract the EGFP-expressing endodermal cells. (E-J) EGFP-expressing endodermal cells are attracted to the cluster of sdf1a- or sdf1b-expressing cells, which are labeled with dextran-Alexa594 (red).