The multifarious role of callose and callose synthase in plant development and environment interactions

Abstract

Callose is an important linear form of polysaccharide synthesized in plant cell walls. It is mainly composed of β-1,3-linked glucose residues with rare amount of β-1,6-linked branches. Callose can be detected in almost all plant tissues and are widely involved in various stages of plant growth and development. Callose is accumulated on plant cell plates, microspores, sieve plates, and plasmodesmata in cell walls and is inducible upon heavy metal treatment, pathogen invasion, and mechanical wounding. Callose in plant cells is synthesized by callose synthases located on the cell membrane. The chemical composition of callose and the components of callose synthases were once controversial until the application of molecular biology and genetics in the model plant Arabidopsis thaliana that led to the cloning of genes encoding synthases responsible for callose biosynthesis. This minireview summarizes the research progress of plant callose and its synthetizing enzymes in recent years to illustrate the important and versatile role of callose in plant life activities.

Callose in leptoid cell walls of the moss Polytrichum and the evolution of callose synthase across bryophytes

“…The evolution of callose synthases (CalS) is well-characterized in tracheophytes but is lesser known in bryophytes ( Schuette et al., 2009 ; Záveská Drábková and Honys, 2017 ; Li et al., 2023 ). In Arabidopsis thaliana there are 12 members of the CalS gene clade that catalyze the synthesis of callose at different stages of development, in different tissues and in response to different environmental stimuli.…”

“…Because cell wall structure and composition are closely linked to many biological processes in plants ( Amsbury et al., 2016 ), a deeper understanding of cell walls in physiologically significant cells such as those involved in translocation of photosynthate is essential to better understand structure-function relationships in mosses. Callose is a versatile cell wall polymer that plays a role in many essential plant functions involved in development and defense, including cell plate formation ( Verma and Hong, 2001 ; Thiele et al., 2009 ), sieve pore development and regulation ( Chen and Kim, 2009 ), transport through plasmodesmata ( Iglesias and Meins, 2000 ; Wang et al., 2022 ; Li et al., 2023 ), pollen development and growth ( McCormick, 1993 ; Chen and Kim, 2009 ), and biotic and abiotic stress responses ( Bacic et al., 2009 ). This cell wall polymer is synthesized in specific tissues during plant growth and development.…”

Repeated global adaptation across plant species

“…Terpenes are metabolites involved in plant defence against both pathogens and herbivores, and are responsible for the attraction of beneficial organisms such as pollinators and seed dispersers (57,58). Similarly, TGSL12 (CALLOSE SYNTHASE 3) is a protein that participates in callose metabolism, a polysaccharide synthesized in the cell wall of a variety of higher plants in 6 response to pathogens infections and abiotic stress (59). The extensively studied cytochrome P450, belongs to a large family of proteins involved in NADPH-and O2-dependent hydroxylation reactions across all domains of life and is closely linked to environmental stress response in plants (60).…”

Genome-Wide Identification of Callose Synthase Family Genes and Their Expression Analysis in Floral Bud Development and Hormonal Responses in Prunus mume

“…Additionally, callose is found localized in phloem sieve plates and at the cell plasmodesmata to regulate the permeability of phloem and the intercellular transport of water, nutrients, and signal molecules [ 5 ]. Under stress conditions such as wounding or pathogen infection, callose quickly accumulates, blocking the sieve pores and plasmodesmata, thereby acting as physical barrier to prevent the penetration of the pathogen and seal injured tissues [ 6 ].…”

“…The knockdown of PbrCalS5 leads to decreased callose deposition in pollen tube walls and subsequent inhibition of pollen tube growth, indicating its role in pear pollen tube growth [ 20 ]. On the other hand, the GSLs also participate in plant adaptive responses to environmental cues [ 6 ]. Under short day conditions, high levels of ABA trigger the expression of callose synthase 1 , which results in increased callose synthesis and deposition at plasmodesmata in poplar shoot tips [ 21 , 22 ].…”