VRN1-associated proteins in Arabidopsis thaliana

The epigenetic silencing of the Arabidopsis floral repressor gene FLOWERING LOCUS C (FLC) is induced by a prolonged period of cold and promotes the developmental transition to flowering post-cold. FLC silencing requires the function of VRN1, a non-sequence-specific DNA binding protein. Here, we used Arabidopsis seedlings growing at ambient temperature carrying a FLAG-tagged VRN1 under its endogenous promoter in the vrn1FRI mutant background. We performed FLAG immunoprecipitation followed by mass spectrometry (IP-MS) on crosslinked tissue. The proteomics analysis revealed several proteins that support the role of VRN1 as a chromatin regulator. The identified proteins associated with VRN1 in vivo also support its contribution to gene silencing.