The bps1 root is sufficient to repress WUS expression in wild-type scions. A, Analysis of shoot expression of pSTM::GUS, pWUS::GUS, and pCLV3::GUS in 5-d wild-type plants that were intact or in scions that were applied to the agarose grafting apparatus but no root or coupled to wild-type or bps1 roots. GUS staining was carried out 24 h after transient graft establishment. Bars = 50 µm. B, Quantitative analysis of STM, WUS, and CLV3 expression in 5-d wild-type shoots transiently grafted to either a wild-type (Col-0) or bps1-2 root. Data are shown as the mean ± sd of three biological and two technical replicates.