Metabolism of Stone Fruits: Reciprocal Contribution Between Primary Metabolism and Cell Wall

Abstract

Cell wall turnover and modification in its composition are key factors during stone fruit development and patterning. Changes in cell wall disassembly and reassembly are essential for fruit growth and ripening. Modifications in cell wall composition, resulting in the formation of secondary cell walls, are necessary for producing the most distinctive trait of drupes: the lignified endocarp. The contribution of primary metabolism to cell wall synthesis has been investigated in detail, while the knowledge on the contribution of the cell wall to primary metabolites and related processes is still fragmented. In this review, starting from peculiarities of cell wall of drupes cells (in mesocarp and endocarp layers), we discuss the structure and composition of cell wall, processes related to its modification and contribution to the synthesis of primary metabolites. In particular, our attention has been focused on the ascorbate synthesis cell wall-related and on the potential role of cyanogenic compounds in the deposition of the secondary cell wall.

Biosynthesis and Cellular Functions of Tartaric Acid in Grapevines

“…From veraison, phloem unloading into the berry switches from a symplastic route to apoplastic ( Zhang et al, 2006 ), flooding the apoplast with high concentrations of hexoses and other solutes, potentially interrupting TA biosynthesis at the cell wall. Changes in apoplastic solutes affect cell turgor and berry firmness associated with veraison and necessary for ripening ( Wada et al, 2008 ; Keller and Shrestha, 2014 ; Rogiers et al, 2017 ), as also seen in other fruits ( Canton et al, 2020 ).…”

Comparative transcriptomic profiling in the pulp and peel of pitaya fruit uncovers the gene networks regulating pulp color formation

“…The amino acid phenylalanine (Phe) is an example of the interconnection between primary and secondary metabolism because it can be a protein building block or a precursor of some secondary metabolites such as lignin, suberin, flavonoids, and benzenoids, which are essential for plant growth, development, and defense ( Vogt, 2010 ; Pascual et al, 2016 ; Canton et al, 2020 ). Lignin biosynthesis is likely to influence cell wall properties; indeed, phenolics can form crosslinks between cell wall components ( Abdel-Massih et al, 2007 ; Seymour et al, 2008 ).…”

Sucrose Metabolism and Transport in Grapevines, with Emphasis on Berries and Leaves, and Insights Gained from a Cross-Species Comparison

“…In trichomes and stomata, all these compounds can contribute to determining turgor pressure changes, and their relative importance depends on various factors [176,177]. Turgor pressure can potentially affect both cell expansion and symplastic import of material, and both occur in the flesh of fruits before ripening [1,178]. In root tips, a turgor pressure gradient between the phloem and sink cells is an important regulator of symplastic bulk flow of liquid from the phloem [174].…”

“…In developing potato tubers, the S:(G+F) ratio, which could be altered by AI, might also play a role in the regulation of this flow [35]. Whether high turgor pressure assists cell expansion depends on the cell in question and its stage of development [174,175,178]. Cell wall properties can be the critical factor [174,179], and in ripening grape pericarp, cell expansion occurs at low turgor [37,180].…”

“…Cell wall properties can be the critical factor [174,179], and in ripening grape pericarp, cell expansion occurs at low turgor [37,180]. In many ripening fruits, this expansion at low turgor is made possible by changes in the structure of the cell wall during ripening [178].…”