Cellulose synthesis during cell plate assembly

Abstract

The plant cell wall surrounds and protects the cells. To divide, plant cells must synthesize a new cell wall to separate the two daughter cells. The cell plate is a transient polysaccharide-based compartment that grows between daughter cells and gives rise to the new cell wall. Cellulose constitutes a key component of the cell wall, and mutants with defects in cellulose synthesis commonly share phenotypes with cytokinesis-defective mutants. However, despite the importance of cellulose in the cell plate and the daughter cell wall, many open questions remain regarding the timing and regulation of cellulose synthesis during cell division. These questions represent a critical gap in our knowledge of cell plate assembly, cell division and growth. Here, we review what is known about cellulose synthesis at the cell plate and in the newly formed cross-wall and pose key questions about the molecular mechanisms that govern these processes. We further provide an outlook discussing outstanding questions and possible future directions for this field of research.

Outside‐in control – does plant cell wall integrity regulate cell cycle progression?

“…Cellulose, consisting of β (1 → 4)‐linked glucose units, also forms a component of the developing cell wall, with cellulose synthases (CESAs) (located at the nascent plasma membrane) depositing cellulose already detectable during the tubulo‐vesicular membrane network stage (Miart et al , Chen et al ). It is interesting to note that the CESAs remain preferentially localized in the proximity of the expanding cell plate, where the cellulose microfibrils they produce could form a framework allowing deposition of other cell wall components (Miart et al ).…”

“…In Arabidopsis, the callose synthase family has 12 members with callose synthase1 (CSL1)/glucansynthase-like6 (GSL6) and GSL8 being implicated in formation of the new cell wall based on localization studies (GSL6) and mutant phenotypes (GSL8) (Thiele et al 2009). Cellulose, consisting of (1 → 4)-linked glucose units, also forms a component of the developing cell wall, with cellulose synthases (CESAs) (located at the nascent plasma membrane) depositing cellulose already detectable during the tubulo-vesicular membrane network stage (Miart et al 2014, Chen et al 2018. It is interesting to note that the CESAs remain preferentially localized in the proximity of the expanding cell plate, where the cellulose microfibrils they produce could form a framework allowing deposition of other cell wall components (Miart et al 2014).…”

Cell wall traits that influence plant development, immunity, and bioconversion

“…The role of cellulose, the preponderant CW polysaccharide, and the role of the non‐saccharide CW component lignin in development, defense and bioconversion have been well covered by several recent reviews (Chen et al ., ; Liu et al ., ; Meents et al ., ). The classical model of the CW architecture depicts cellulose microfibrils as interconnected at their surface with hemicelluloses in turn embedded in a matrix of pectin, which forms a sort of glue that provides flexibility or stiffness to the CW.…”

From plant cell wall metabolism and plasticity to cell wall biotechnology

“…Chen et al () provide in their review a concise summary of the events and processes leading to formation of a new cell wall separating the daughter cells after division. They focus in particular on the cellular processes taking place and how cellulose production and deposition are regulated and coordinated with them.…”

“…These regulatory mechanisms are intimately interconnected with each other, and further research into their mode of action will result in more detailed insights in plant evolution, ecology and function, possibly leading to biomimetic applications. Chen et al (2018) provide in their review a concise summary of the events and processes leading to formation of a new cell wall separating the daughter cells after division. They focus in particular on the cellular processes taking place and how cellulose production and deposition are regulated and coordinated with them.…”