Cell wall dynamics during apple development and storage involves hemicellulose modifications and related expressed genes

Abstract

BackgroundFruit quality depends on a series of biochemical events that modify appearance, flavour and texture throughout fruit development and ripening. Cell wall polysaccharide remodelling largely contributes to the elaboration of fleshy fruit texture. Although several genes and enzymes involved in cell wall polysaccharide biosynthesis and modifications are known, their coordinated activity in these processes is yet to be discovered.ResultsCombined transcriptomic and biochemical analyses allowed the identification of putative enzymes and related annotated members of gene families involved in cell wall polysaccharide composition and structural changes during apple fruit growth and ripening. The early development genes were mainly related to cell wall biosynthesis and degradation with a particular target on hemicelluloses. Fine structural evolutions of galactoglucomannan were strongly correlated with mannan synthase, glucanase (GH9) and β-galactosidase gene expression. In contrast, fewer genes related to pectin metabolism and cell expansion (expansin genes) were observed in ripening fruit combined with expected changes in cell wall polysaccharide composition.ConclusionsHemicelluloses undergo major structural changes particularly during early fruit development. The high number of early expressed β-galactosidase genes questions their function on galactosylated structures during fruit development and storage. Their activity and cell wall substrate remains to be identified. Moreover, new insights into the potential role of peroxidases and transporters, along with cell wall metabolism open the way to further studies on concomitant mechanisms involved in cell wall assembly/disassembly during fruit development and storage.Electronic supplementary materialThe online version of this article (doi:10.1186/s12870-016-0887-0) contains supplementary material, which is available to authorized users.

Immunoprofiling of Cell Wall Carbohydrate Modifications During Flooding-Induced Aerenchyma Formation in Fabaceae Roots

“…Our research also revealed the presence of de-methylesterified (DME), partially DME and fully methyl-esterified (ME) pectin residues in the cell walls and middle lamella of stele and cortical tissues involved in aerenchyma formation. Previous research proposed that removal of methyl ester substitutions from the homogalacturonan domains of pectin enables degradation of cell walls by unblocking cleavage sites between pectin residues, which are then targeted by polygalacturonases, pectin lyases and similar hydrolytic enzymes (Dheilly et al, 2016). Our observations showed that DME pectin is spatially localized within one to three cell layers around aerenchyma and increases from partial and fully DME during aerenchyma development (Figures 4-7).…”

GC-MS Based Metabolite Profiling to Monitor Ripening-Specific Metabolites in Pineapple (Ananas comosus)

“…Mannose is known as a component of the plant cell wall, specifically hemicellulose [47]. The previous report mentioned that the concentration of mannose was decreased during fruit development, hence support our findings shown in Figure 6b [48]. Similar to mannose, decrease level of aspartic acid in the pineapple ripening process were also reported during ripening of banana [49].…”

Systems-Based Approaches to Unravel Networks and Individual Elements Involved in Apple Superficial Scald

“…Both antisense (AS) and sense (S) probes were designed for each sample, and 16.5% of the significantly expressed probes corresponded to antisense (AS) transcripts (Supplementary Table 5). Previous studies (Dheilly et al, 2016) demonstrated that AS transcripts were likely to be involved in small interfering RNA (siRNA), dependent on the negative regulation of the coding mRNAs. Subsequently, this current study considers only the genes with sense (S) probes as differentially expressed transcripts.…”