Responses of plant cell wall to sub-zero temperatures: a brief update

Authors: TAKAHASKI, DAISUKE - Saitama University; WILLICK, IAN - Michigan State University; KASUGA, JUN - Obihiro University Of Agriculture And Veterinary Medicine; Livingston, David

Submitted to: Plant and Cell Physiology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 12/1/2021
Publication Date: 7/8/2021
Citation: Takahaski, D., Willick, I.R., Kasuga, J., Livingston, D.P. 2021. Responses of plant cell wall to sub-zero temperatures: a brief update. Plant and Cell Physiology. https://doi.org/10.1093/pcp/pcab103.
DOI: https://doi.org/10.1093/pcp/pcab103

Interpretive Summary: Our general understanding of plant responses to sub-zero temperatures focuses on mechanisms that mitigate stress to the plasma membrane. The plant cell wall receives comparatively less attention, and questions surrounding its role in mitigating freezing injury remain unresolved. Despite recent molecular discoveries that provide insight into acclimation responses, the goal of reducing freezing injury in herbaceous and woody crops remains elusive. This is likely due to the complexity associated with adaptations to low temperatures. Understanding how leaf cell walls of herbaceous annuals promote tissue tolerance to ice does not necessarily lead to understanding how meristematic tissues are protected from freezing by tissue-level barriers formed by cell walls in overwintering tree buds. In this mini-review, we provide an overview of biological ice nucleation and explain how plants control the spatiotemporal location of ice formation. We discuss how sugars and pectin side chains alleviate adhesive injury that develops at sub-zero temperatures between the matrix polysaccharides and ice. The importance of site-specific cell-wall elasticity to promote tissue expansion for ice accommodation and control of porosity to impede ice growth and promote supercooling will be presented. How specific cold-induced proteins modify plant cell walls to mitigate freezing injury will also be discussed. The opinions presented in this report emphasize the importance of a plant’s developmental physiology when characterizing mechanisms of freezing survival.

Technical Abstract: Our general understanding of plant responses to sub-zero temperatures focuses on mechanisms that mitigate stress to the plasma membrane. The plant cell wall receives comparatively less attention and questions surrounding its role in alleviating freezing injury remain unresolved. Despite recent molecular discoveries that provide insight into acclimation responses, the goal of reducing freezing injury in herbaceous and woody crops remains elusive. This is likely due to the complexity associated with adaptations to low temperatures. Understanding how herbaceous annual leaf cell walls promote tolerance towards tissue ice may not provide the needed context for how cell walls in overwintering tree buds form tissue level barriers so that meristem tissues can avoid freezing by supercooling. In this mini review, we provide an overview of biological ice nucleation and explain how plants control the spatiotemporal location of ice aggregation. We discuss how sugars and pectin side chains alleviate adhesive injury that develops at sub-zero temperatures between the matrix polysaccharides and ice. The importance of site-specific cell wall elasticity to promote tissue expansion for ice accommodation and control of porosity to impede ice growth and promote supercooling. How specific cold-induced proteins modify plant cell walls to mitigate freezing injury will also be discussed. The opinions presented in this report emphasize the importance of a plant’s developmental physiology when characterizing mechanisms of freezing survival.