Binds A/T-rich DNA (e.g. present in the storage gamma-zein gene promoter) with a highly dynamic distribution into the nucleus (PubMed:19781672, PubMed:10864924). Probably involved in endosperm development, during cells shift from a mitotic cycle to endoreduplication leading to massive synthesis of storage proteins (zeins) and starch (PubMed:10864924). Follows a highly dynamic speckled distribution pattern throughout the chromatin of interphase nuclei. Phosphorylated by CDK, this phosphorylation prevents DNA-binding (PubMed:19781672, PubMed:10864924). Motility is increased when hypophosphorylated (PubMed:10864924). Acetylated. Confers resistance to nickel NiSO(4) when expressed in yeast (e.g. S.cerevisiae) by counterbalancing nickel impact on cell cycle associated with an increased chromatin condensation. Belongs to the histone H1/H5 family.