Aufklärung der Mechanismen der Chitin-Faser-Orientierung in Arthropodenkutikula

01/01/2015 to 31/12/2019

Arthropod cuticles are composed of several layers of α-chitin nanofibrils embedded in a protein matrix. The orientation of the chitin fibers within each layer is strongly correlated with the mechanical properties of the cuticle and has a strong effect the degree of water sorption in that layer. Hence, a precise control of the chitin orientation during the growth of the cuticle is crucial to determine the biomechanical properties of the cuticle. So far the detailed control-mechanisms of chitin orientation in insect cuticle are not fully understood. In particular very little is known about the cross-talk between cell-mediated co-orientation of the fibers and self-assembly processes. Here we propose to address this question using x-ray scattering and microscopy techniques on samples of freshly formed insect cuticle. Locusts deposit cuticle with distinct daily growth layers of alternating parallel (day) and helicoidal chitin fibers (night). By collecting samples at defined times intervals after a “switch”, we can perform a detailed “quasi-real-time” investigation of both types of cuticles and investigate the biochemical pathways of chitin fibre alignment in arthropod cuticle.