Sequence-encoded material properties dictate the structure and function of nuclear bodies

•Nuclear bodies (NBs) are phase-separated membraneless organelles.•Amino acid sequences of NB components confer liquid-like or solid-like behavior.•Differences in material properties of immiscible phases drive core/shell structure.•Concentration of enzymes within NBs can enhance or inhibit their function.

Concomitant with packaging the genome, the cell nucleus must also spatially organize the nucleoplasm. This complex mixture of proteins and nucleic acids partitions into a variety of phase-separated, membraneless organelles called nuclear bodies. Significant progress has been made in understanding the relationship between the material properties of nuclear bodies and their structural and functional consequences. Furthermore, the molecular basis of these condensed phases is beginning to emerge. Here, I review the latest work in this exciting field, highlighting recent advances and new challenges.