The cell wall and control of cell growth

1990 ◽  
pp. 89-113 ◽  
Author(s):  
C. Brett ◽  
K. Waldron
Keyword(s):  
Cell Wall ◽  
Cell Growth ◽  
And Control

scholarly journals Transcriptomics of Improved Fruit Retention by Hexanal in ‘Honeycrisp’ Reveals Hormonal Crosstalk and Reduced Cell Wall Degradation in the Fruit Abscission Zone

2021 ◽  
Vol 22 (16) ◽  
pp. 8830
Author(s):  
Karthika Sriskantharajah ◽  
Walid El Kayal ◽  
Davoud Torkamaneh ◽  
Murali M. Ayyanath ◽  
Praveen K. Saxena ◽  
...  
Keyword(s):  
Cell Wall ◽  
Ethylene Biosynthesis ◽  
Abscission Zone ◽  
Cell Wall Degrading Enzymes ◽  
Fruit Abscission ◽  
Fruit Drop ◽  
Expression Of Genes ◽  
Hormonal Crosstalk ◽  
Honeycrisp Apples ◽  
And Control

Apples (Malus domestica Borkh) are prone to preharvest fruit drop, which is more pronounced in ‘Honeycrisp’. Hexanal is known to improve fruit retention in several economically important crops. The effects of hexanal on the fruit retention of ‘Honeycrisp’ apples were assessed using physiological, biochemical, and transcriptomic approaches. Fruit retention and fruit firmness were significantly improved by hexanal, while sugars and fresh weight did not show a significant change in response to hexanal treatment. At commercial maturity, abscisic acid and melatonin levels were significantly lower in the treated fruit abscission zone (FAZ) compared to control. At this stage, a total of 726 differentially expressed genes (DEGs) were identified between treated and control FAZ. Functional classification of the DEGs showed that hexanal downregulated ethylene biosynthesis genes, such as S-adenosylmethionine synthase (SAM2) and 1-aminocyclopropane-1-carboxylic acid oxidases (ACO3, ACO4, and ACO4-like), while it upregulated the receptor genes ETR2 and ERS1. Genes related to ABA biosynthesis (FDPS and CLE25) were also downregulated. On the contrary, key genes involved in gibberellic acid biosynthesis (GA20OX-like and KO) were upregulated. Further, hexanal downregulated the expression of genes related to cell wall degrading enzymes, such as polygalacturonase (PG1), glucanases (endo-β-1,4-glucanase), and expansins (EXPA1-like, EXPA6, EXPA8, EXPA10-like, EXPA16-like). Our findings reveal that hexanal reduced the sensitivity of FAZ cells to ethylene and ABA. Simultaneously, hexanal maintained the cell wall integrity of FAZ cells by regulating genes involved in cell wall modifications. Thus, delayed fruit abscission by hexanal is most likely achieved by minimizing ABA through an ethylene-dependent mechanism.

scholarly journals Thermodynamics of irreversible plant cell growth

2011 ◽  
Vol 75 (3) ◽  
pp. 183-190 ◽  
Author(s):  
Mariusz Pietruszka ◽  
Sylwia Lewicka ◽  
Krystyna Pazurkiewicz-Kocot
Keyword(s):  
Cell Wall ◽  
Cell Growth ◽  
Water Absorption ◽  
Abiotic Factors ◽  
Plant Cells ◽  
Wall Stress ◽  
Growth Equation ◽  
Experimental Conditions ◽  
Linear Solution ◽  
Non Linear

The time-irreversible cell enlargement of plant cells at a constant temperature results from two independent physical processes, e.g. water absorption and cell wall yielding. In such a model cell growth starts with reduction in wall stress because of irreversible extension of the wall. The water absorption and physical expansion are spontaneous consequences of this initial modification of the cell wall (the juvenile cell vacuolate, takes up water and expands). In this model the irreversible aspect of growth arises from the extension of the cell wall. Such theory expressed quantitatively by time-dependent growth equation was elaborated by Lockhart in the 60's.The growth equation omit however a very important factor, namely the environmental temperature at which the plant cells grow. In this paper we put forward a simple phenomenological model which introduces into the growth equation the notion of temperature. Moreover, we introduce into the modified growth equation the possible influence of external growth stimulator or inhibitor (phytohormones or abiotic factors). In the presence of such external perturbations two possible theoretical solutions have been found: the linear reaction to the application of growth hormones/abiotic factors and the non-linear one. Both solutions reflect and predict two different experimental conditions, respectively (growth at constant or increasing concentration of stimulator/inhibitor). The non-linear solution reflects a common situation interesting from an environmental pollution point of view e.g. the influence of increasing (with time) concentration of toxins on plant growth. Having obtained temperature modified growth equations we can draw further qualitative and, especially, quantitative conclusions about the mechanical properties of the cell wall itself. This also concerns a new and interesting result obtained in our model: We have calculated the magnitude of the cell wall yielding coefficient (T) [m<sup>3</sup> J<sup>-1</sup>•s<sup>-1</sup>] in function of temperature which has acquired reasonable numerical value throughout.

The yeast KRE5 gene encodes a probable endoplasmic reticulum protein required for (1----6)-beta-D-glucan synthesis and normal cell growth

1990 ◽  
Vol 10 (6) ◽  
pp. 3013-3019
Author(s):  
P Meaden ◽  
K Hill ◽  
J Wagner ◽  
D Slipetz ◽  
S S Sommer ◽  
...  
Keyword(s):  
Endoplasmic Reticulum ◽  
Cell Wall ◽  
Cell Growth ◽  
Normal Cell ◽  
Secretory Pathway ◽  
Endoplasmic Reticulum Retention Signal ◽  
Endoplasmic Reticulum Protein ◽  
Glucan Synthesis ◽  
Retention Signal ◽  
Sequential Assembly

Yeast kre mutants define a pathway of cell wall (1----6)-beta-D-glucan synthesis, and mutants in genes KRE5 and KRE6 appear to interact early in such a pathway. We have cloned KRE5, and the sequence predicts the product to be a large, hydrophilic, secretory glycoprotein which contains the COOH-terminal endoplasmic reticulum retention signal, HDEL. Deletion of the KRE5 gene resulted in cells with aberrant morphology and extremely compromised growth. Suppressors to the KRE5 deletions arose at a frequency of 1 in 10(7) to 1 in 10(8) and permitted an analysis of deletions which were found to contain no alkali-insoluble (1----6)-beta-D-glucan. These results indicate a role for (1----6)-beta-D-glucan in normal cell growth and suggest a model for sequential assembly of (1----6)-beta-D-glucan in the yeast secretory pathway.

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