Do Cuticular Gaps Make It Possible to Study the Composition of the Cell Walls in the Glands of Drosophyllum lusitanicum?

Abstract

Carnivorous plants can survive in poor habitats because they have the ability to attract, capture, and digest prey and absorb animal nutrients using modified organs that are equipped with glands. These glands have terminal cells with permeable cuticles. Cuticular discontinuities allow both secretion and endocytosis. In Drosophyllum lusitanicum, these emergences have glandular cells with cuticular discontinuities in the form of cuticular gaps. In this study, we determined whether these specific cuticular discontinuities were permeable enough to antibodies to show the occurrence of the cell wall polymers in the glands. Scanning transmission electron microscopy was used to show the structure of the cuticle. Fluorescence microscopy revealed the localization of the carbohydrate epitopes that are associated with the major cell wall polysaccharides and glycoproteins. We showed that Drosophyllum leaf epidermal cells have a continuous and well-developed cuticle, which helps the plant inhibit water loss and live in a dry environment. The cuticular gaps only partially allow us to study the composition of cell walls in the glands of Drosophyllum. We recoded arabinogalactan proteins, some homogalacturonans, and hemicelluloses. However, antibody penetration was only limited to the cell wall surface. The localization of the wall components in the cell wall ingrowths was missing. The use of enzymatic digestion improves the labeling of hemicelluloses in Drosophyllum glands.

Cell Wall Microdomains in the External Glands of Utricularia dichotoma Traps

“…This issue requires further research. AGPs were found in cell wall ingrowths in cells of glands of various species of carnivorous plants: Aldrovanda [ 82 , 83 ], Dionaea [ 84 , 85 ], and Drosophyllum [ 86 , 87 ]. AGPs were also found in Drosera glands’ cells [ 88 ].…”

“…The traps were fixed as in Płachno et al [ 83 , 84 ]. For analysis of the occurrence of the major cell wall polysaccharides and glycoproteins, the plant material was dehydrated with acetone and embedded in an Epoxy Embedding Medium Kit (Fluka) and later processed as in Płachno et al [ 86 , 87 ]. The following primary antibodies were used: anti-AGP—JIM8, JIM13, JIM14, MAC207, and JIM4 [ 96 , 97 , 98 , 99 , 100 ].…”

Do Arabinogalactan Proteins Occur in the Transfer Cells of Utricularia dichotoma?

“…AGPs were found in cell wall ingrowths of various species [ 25 , 26 , 27 , 28 , 55 , 56 ]. AGPs were also found in cell wall ingrowths of various glands from traps of carnivorous plants from the genera Aldrovanda [ 57 , 58 ], Dionaea [ 59 , 60 ], and Drosophyllum [ 61 , 62 ]. According to Płachno and Kapusta [ 29 ], the presence of AGPs in the cell wall of terminal cells may be related to processes of endocytosis and exocytosis (involving vesicle trafficking and membrane recycling), in which these proteins participate [ 51 , 63 , 64 ].…”