ILP1 Functions as a Transcriptional Repressor in Plant Cells.
(A) The constructs used for the in vivo transcription assay. GAL4-ILP1N, GAL4 DNA binding domain (GAL4DB) is fused to the N-terminal region of ILP1 (residues 1 to 567); GAL4-ILP1C, GAL4DB is fused to the C-terminal region of ILP (residues 474 to 908); GAL4ILP1Full, GAL4DB is fused to the full-length ILP1. The reporter plasmid contains a GAL4 binding site and 0.2 kb of the nopaline synthase promoter (NOS-pro) upstream of the LUC reporter gene. The reference plasmid serves to monitor the transformation efficiency by β-glucuronidase (GUS) expression controlled by a constitutive CaMV 35S promoter.
(B) In vivo transcription assay in tobacco leaves. LUC/GUS ratio: LUC expression (reporter) was normalized with GUS expression (reference). Error bars indicate standard error. The experiment was repeated five times.