Updating Insights into the Catalytic Domain Properties of Plant Cellulose synthase (CesA) and Cellulose synthase-like (Csl) Proteins

Abstract

The wall is the last frontier of a plant cell involved in modulating growth, development and defense against biotic stresses. Cellulose and additional polysaccharides of plant cell walls are the most abundant biopolymers on earth, having increased in economic value and thereby attracted significant interest in biotechnology. Cellulose biosynthesis constitutes a highly complicated process relying on the formation of cellulose synthase complexes. Cellulose synthase (CesA) and Cellulose synthase-like (Csl) genes encode enzymes that synthesize cellulose and most hemicellulosic polysaccharides. Arabidopsis and rice are invaluable genetic models and reliable representatives of land plants to comprehend cell wall synthesis. During the past two decades, enormous research progress has been made to understand the mechanisms of cellulose synthesis and construction of the plant cell wall. A plethora of cesa and csl mutants have been characterized, providing functional insights into individual protein isoforms. Recent structural studies have uncovered the mode of CesA assembly and the dynamics of cellulose production. Genetics and structural biology have generated new knowledge and have accelerated the pace of discovery in this field, ultimately opening perspectives towards cellulose synthesis manipulation. This review provides an overview of the major breakthroughs gathering previous and recent genetic and structural advancements, focusing on the function of CesA and Csl catalytic domain in plants.

Point mutations in the catalytic domain disrupt cellulose synthase (CESA6) vesicle trafficking and protein dynamics

“…In contrast, the DDG motif is likely to be nonessential for CESA catalytic activity, or it could be that a single mutation in the DDG motif is not sufficient to cause any measurable effect on motility. The DDG motif is thought to coordinate the donor UDP-glucose molecule at the catalytic site (Purushotham et al, 2020; Daras et al, 2021; Supplemental Table S2).…”

“…Arabidopsis cesa mutants carrying missense mutations are valuable tools for understanding the molecular and cellular mechanisms underlying cellulose biosynthesis (McFarlane et al, 2014; Daras et al, 2021). All 18 AtCESA6 mutations created here affected cellulose biosynthesis (Figure 1E, Supplemental Table S3), and were predicted to interfere with catalytic activity by disrupting UDP-glucose binding, glucan chain elongation, or glucan chain translocation (Supplemental Table S2).…”

“…In addition to these key motifs, several other mutations including P595S, D602N, D605N and G632D also caused significant reductions in CSC motility and increased the abundance of pause-forever CSCs. The conserved P595 is located in a previously undescribed motif near the catalytic core (Daras et al, 2021) and mutations of this region in other CESA isoforms show similar phenotypes compared to AtCESA6 P595S , originally described as es20r10 (Huang et al, 2020). For example, analogous mutations of AtCESA3 ( repp3/thanatos , AtCESA3 P578L/S ) and AtCESA7 ( fra5 , AtCESA7 P557S ) cause severe growth defects and cellulose biosynthesis deficiencies (Zhong et al, 2003; Daras et al, 2009; Feraru et al, 2011).…”

Receptor Kinases: A Sophisticate Protein Network to Maintain Plant life Continuity. An Update

“…Molecular analysis reveals that overexpression of CLE peptides leads to retardation of root growth and premature root meristem differentiation that indicates a pathway related to CLV [47,48]. Similarly, it has been reported that a gene family member of cellulose synthase CESA1/RSW1 regulates the growth of root and shoot cell walls and determines cell shape during cell division and expansion in embryo cells of Arabidopsis [49]. During research on RLCKs function in rice callus, Sun, et al in 2015 found that a temperature sensitive 290-kDa complex OsSec18 in rice embryo cells facilitating a conserved ATPase protein, plays important role in plant height and 1000-grain seed weight.…”

Transcriptome Analysis of Sugarcane Young Leaves and Protoplasts after Enzymatic Digestion

“…Galacturonic acid transferase (Galacturonosyltransferase, GAUT) is the key enzyme catalyzing UDP-galacturonic acid to form homogalacturonan frame in pectin bio-synthesis [ 25 , 26 ]. Cellulose synthase (CesAs) and cellulose synthase-like (Csl) genes encode enzymes that synthesize cellulose and most hemicellulosic polysaccharides [ 27 ]. Loss of GAUT function in the synthesis of pectin and xylan in 15 wild-type Arabidopsis species affects plant cell wall production [ 28 ].…”