Fig. 7. BMP suppresses Edar but not Eda. (A) An embryo infected with a virus that encodes BMP4 shows suppression of Edar in the feather tract where bud formation is suppressed (black arrows), and no effect ahead of the morphogenetic wave or in the pseudoapteria (red arrows). (B) Detection of viral transcripts reveals infection in the areas where bud formation is suppressed (black arrows), as well as in the lateral regions of the flank (red arrows). (C) An infected embryo shows maintenance of the diffuse expression of Eda in an area of suppressed bud formation that would normally exhibit the honeycomb pattern of expression at this stage (black arrow). No alteration of Eda expression is observed ahead of the morphogenetic wave or in the pseudoapteria (red arrows). (D) Subsequent detection of viral transcripts demonstrates infection in the areas of bud suppression (black arrow), as well as in the lateral regions indicated in C (red arrows).