In plants, cells can neither move nor reorganize freely due to their rigid walls. How, then, do they correctly orient their division to build coherent tissues - A study published in Science Advances reveals that, in addition to an already well-documented classical cue, plant cells rely on the actin cytoskeleton to adjust the plane of division according to their environment.
The preprophase stripe, a classic but not indispensable landmark
When a cell divides, the orientation of the division plane plays a decisive role in tissue organization and development. In plants, this stage is particularly delicate, as the cells are surrounded by rigid walls and remain fixed in their positions during development.
Traditionally, the orientation of cell division in plants has been associated with the formation of the preprophase band, a transient structure composed of microtubules that marks the future site of division before entry into mitosis. This band has long been considered an indispensable landmark. However, previous studies have shown that cells lacking the preprophase band can still divide in a generally correct orientation.
The actin cytoskeleton as a back-up system
To understand this robustness, scientists have published a study in the journal Science Advances in which they studied the division of plant cells subjected to different geometric constraints. Combining high-resolution microscopy, genetic manipulations, pharmacological perturbations and quantitative modeling, they revealed a complementary mechanism based on the actin cytoskeleton.
Reference
Camila Goldy et al, The actin cytoskeleton is required to maintain plant cell division orientation against cellular geometry. Sci. Adv. 12,eaeb8498(2026). DOI: 10.1126/sciadv.aeb8498
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