Genome-wide analyses define distinct functions for the florigen interacting bZIP transcription factors FD and FDP in abscisic acid responses and flowering of Arabidopsis.

In plants, bZIP transcription factors interact with systemically transported PHOSPHATIDYL ETHANOLAMINE BINDING PROTEINs (PEPB) to activate genes conferring seasonal responses to day length. Flowering of Arabidopsis under long days involves the bZIP proteins FLOWERING LOCUS D (FD) and FLOWERING LOCUS D PARALOGUE (FDP) and the PEPBs FLOWERING LOCUS T (FT) and TWIN SISTER OF FT (TSF). We generated null alleles of FDP with CRISPR-cas9, analyzed the specificity of FD and FDP using genome-wide ChIPseq and RNAseq approaches and described their expression patterns with confocal microscopy.