Component of the SWR1 complex which mediates the ATP- dependent exchange of histone H2A for the H2A variant H2A.F/Z leading to transcriptional regulation of selected genes (e.g. FLC) by chromatin remodeling. Required for the activation of FLC and FLC/MAF genes expression to levels that inhibit flowering, through both histone H3 and H4 acetylation and methylation mechanisms. Involved in several developmental processes including organization of plant organs, leaves formation, flowering time repression, and fertility. Modulates photoperiod-dependent epidermal leaves cell development\; promotes cell division in long days, and cell expansion/division in short days. May be involved in the regulation of pathogenesis-related proteins (PRs).