Histone binding-protein that regulates chromatin dynamics and minichromosome maintenance (MCM) loading at replication origins, possibly by promoting chromatin openness. Interacts with METTL18. Interacts with CDT1; origin binding of GRWD1 is dependent on CDT1. Interacts with CDC6; origin binding of GRWD1 is dependent on CDC6. Binds to histone H2A-H2B and H3-H4 complexes. Present in the nucleus throughout interphase and is detached from chromatin at the onset of mitosis and rebinds at telophase when the pre-replication complexes (pre-RC) is formed.