Details

Autor(en) / Beteiligte

• Seidl, Bastian
• Reisecker, Christian
• Neues, Frank
• Campanaro, Alessandro
• Epple, Matthias
• Hild, Sabine
• Ziegler, Andreas

Titel

The dorsal tergite cuticle of Helleria brevicornis: Ultrastructure, mineral distribution, calcite microstructure and texture

Ist Teil von

• Journal of structural biology. X, 2021-01, Vol.5, p.100051-100051, Article 100051

Ort / Verlag

Elsevier Inc

Erscheinungsjahr

2021

Link zum Volltext

Quelle

Alma/SFX Local Collection

Beschreibungen/Notizen

• [Display omitted] •Two types, long and short, tricorn sensilla on the tergites have unusual brushed tips.•Calcite is restricted to the distal exocuticle; the subjacent layers contain ACC.•The distal exocuticle contains interprismatic septa.•Calcite units do not follow the hexagonal pattern of the interprismatic septa.•The septa help to control the size and shape of co-oriented calcite units. Among the terrestrial Crustacea, isopods have most successfully established themselves in a large variety of terrestrial habitats. As in most Crustacea, their cuticle consists of a hierarchically organised organic phase of chitin-protein fibrils, containing calcium carbonate and some calcium phosphate. In previous studies, we examined the tergite cuticle of Tylos europaeus, which lives on seashores and burrows into moist sand. In this study, we investigate the closely related species Helleria brevicornis, which is completely terrestrial and lives in leaf litter and humus and burrows into the soil. To get deeper insights in relation between the structure of the organic and mineral phase in species living in diverse habitats, we have investigated the structure, and the chemical and crystallographic properties of the tergite cuticle using various preparation techniques, and microscopic and analytical methods. The results reveal long and short epicuticular sensilla with brushed tips on the tergite surface that do not occur in T. europaeus. As in T. europaeus a distal exocuticle, which contains a low number of organic fibres, contains calcite while the subjacent layers of the exo- and endocuticle contain amorphous calcium carbonate. The distal exocuticle contains a polygonal pattern of mineral initiation sites that correspond to interprismatic septa described for decapod crabs. The shape and position of calcite units do not follow the polygonal pattern of the septa. The results indicate that the calcite units form by crystallisation from an amorphous phase that progresses from both margins of the septa to the centres of the polygons.