| Abstract
| - The crispness of fruits and vegetables is dependent, predominantly, on the maintenance of celladhesion. There is a growing body of evidence to suggest that cell adhesion in plants is controlledat the edge of cell faces rather than across the entire cell surface. The aim of the current study hasbeen to exploit antibody-labeling techniques in conjunction with methods that induce cell separationto explore the distribution of highly esterified and weakly esterified pectic polysaccharides on thecell surface. Potato parenchyma tissue was subjected to cooking and chemical treatments, whichinduced softening through cell separation. Scanning electron microscopy (SEM) revealed characteristic patterns on the surface of these separated cells, which outlined the imprint of neighboringcells. Monoclonal antibodies, JIM5 and JIM7, were used to locate weakly esterified and highlyesterified pectin by silver-enhanced immunogold SEM. The edge-of-face structures labeled stronglywith JIM5 but not JIM7, indicating that they contained polygalacturonic acid of low ester content.In addition, adhesion of the middle lamella to the face of the primary wall was found to differ fromadhesion at the edge of each cell face. This, in conjunction with the antibody-labeling observations,complements previous transmission electron microscopy studies and is consistent with the edge-of-face regions having a specialist role in cell adhesion. Keywords: Antibody (JIM5, JIM7); cell wall, cell adhesion, pectic polysaccharide; potato; Solanumtuberosum; texture
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