Nuclear Entanglement: New Insights Into the Role of Cytoskeleton and Nucleoskeleton in Plant Nuclear Function

Of the three types of cytoskeleton known in animals-actin, microtubules, and intermediate filaments-only actin and microtubules exist in plants. Both play important roles in cellular shaping, organelle movement, organization of the endomembrane system, and cell signaling. An emerging, but often overlooked role of the plant cytoskeleton is its dynamic and mutually influential interaction with the nucleus. Here, we summarize recent advances in understanding the role of the cytoskeleton in plant nuclear movement in different biological contexts, a role for nuclear envelope-associated proteins in reorganizing the actin and microtubule cytoskeleton, and the molecular nature of the nucleus-cytoskeleton interface and specific proteins contributing to it. In animals, the nucleoskeleton consists of the nuclear lamina, an intermediate-filament meshwork underlying the nuclear envelope. Plants have evolved an equivalent of this structure, built by different types of proteins. Here, we highlight recent advances in understanding its filamentous organization, newly discovered protein interactions connecting it to nuclear pores, and exciting new evidence that-just like the animal lamina-the plant lamina is involved in chromatin reorganization and epigenetic changes. Together, these new developments create new opportunities toward a deeper understanding of this important regulatory connection between the cytoskeleton and the cell's largest organelle.