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Abstract The nuclear lamina in plant cells is composed of plant-specific proteins, including nuclear matrix constituent proteins (NMCPs), which have been postulated to be functional analogs of lamin proteins that provide structural integrity to the organelle and help stabilize the three-dimensional organization of the genome. Using genomic editing, we generated alleles for the three genes encoding NMCPs in cultivated tomato (Solanum lycopersicum) to determine if the consequences of perturbing the nuclear lamina in this crop species were similar to or distinct from those observed in the model Arabidopsis thaliana. Loss of the sole NMCP2-class protein was lethal in tomato but is tolerated in Arabidopsis. Moreover, depletion of NMCP1-type nuclear lamina proteins leads to distinct developmental phenotypes in tomato, including leaf morphology defects and reduced root growth rate (in nmcp1b mutants), compared with cognate mutants in Arabidopsis. These findings suggest that the nuclear lamina interfaces with different developmental and signaling pathways in tomato compared with Arabidopsis. At the subcellular level, however, tomato nmcp mutants resembled their Arabidopsis counterparts in displaying smaller and more spherical nuclei in differentiated cells. This result argues that the plant nuclear lamina facilitates nuclear shape distortion in response to forces exerted on the organelle within the cell.
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This content will become publicly available on June 5, 2026
Nuclear Entanglement: New Insights Into the Role of Cytoskeleton and Nucleoskeleton in Plant Nuclear Function
ABSTRACT 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.
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- Award ID(s):
- 2023348
- PAR ID:
- 10598587
- Publisher / Repository:
- Wiley
- Date Published:
- Journal Name:
- Cytoskeleton
- ISSN:
- 1949-3584
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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