Fig. S4

Distinguishing between transplanted muscle pioneers and transplanted endothelial cells. (A) Heterochronic transplant scheme used for this test: donor is labeled with Rhodamine Dextran (RhDx) and both donor and host are marked with fli1a:egfp^y1. (B-D) Live lateral views of a 48 hpf transplanted embryo. There are three classes of RhDx-positive cells at the HMS. (1) A RhDx⁺ GFP^- cell. This is a transplanted muscle pioneer (MP, white arrow). (2) A RhDx⁺ GFP⁺ cell in which the GFP and RhDx fluorescence coincide. This is a transplanted endothelial cell (EC, yellow arrow). (3) A RhDx⁺ cell adjacent to, but not coinciding with, a GFP⁺ cell. This is a transplanted MP adjacent to a host EC (blue arrow). For rescue experiments in which the host was not marked with fli1a:egfp^y1, class 3 combines with class 1; however, it is still possible to distinguish between transplanted MPs and transplanted ECs by looking for coincident GFP expression from the donor fli1a:egfp^y1 transgene.