Figure 1

TDIF and CLE42 interact with PXY^LRR, PXL1^LRR and PXL2^LRR in vitro. (A) Both GST-TDIF and GST-CLE42 can pull-down the PXY^LRR, PXL1^LRR and PXL2^LRR proteins. The purified PXY^LRR, PXL1^LRR or PXL2^LRR was incubated with GS4B resin bound by GST-TDIF or GST-CLE42. After extensive washing, the GS4B resin-bound proteins were analyzed by SDS-PAGE and detected by Coomassie blue staining. (B) Measurement of binding affinity between PXY^LRR and TDIF by ITC. Top panel: twenty injections of TDIF solution were titrated into PXY^LRR solution in the ITC cell. The area of each injection peak corresponds to the total heat released for that injection. Bottom panel: the binding isotherm for PXY^LRR and TDIF interaction, the integrated heat is plotted against the molar ratio between TDIF and PXY^LRR. Data fitting revealed a binding affinity of about 33 nM. (C) Sequence alignment of CLE peptide family from Arabidopsis thaliana. Conserved and similar residues are boxed with red ground and red font, respectively.