Fig. 6

Expression and protein–protein interaction of annotated and IR isoforms of light-regulated transcription factors. a Illustrations of mRNA and protein isoforms for light-regulated transcription factors in annotated (black) and isoforms with retained intron (IR) (blue). Right panel shows the relative expression of annotated and IR transcripts in D4h and L4h samples. The 5 IR transcripts of the light-regulated transcription factors BBX22IR, BBX24IR, PIF3IR, PIF4IR, and HY5IR were selected. White boxes, filled boxes, and lines represent the untranslated regions, coding sequences (CDS), and introns, respectively. Forward and reverse primers are marked with arrowheads. Recognizable domains of the deduced proteins are marked. Total transcript levels for each transcript in the L4h sample were set to 100%. b Protein–protein interaction analyses of 5 light-regulated transcription factors between annotated and their IR forms by yeast two-hybrid assays