Parts | Days | Selection | Search | Updates | Downloads | Help
BP: Fachverband Biologische Physik
BP 24: Cell adhesion and migration, multicellular systems I
BP 24.5: Talk
Thursday, April 4, 2019, 10:45–11:00, H11
External forces generated by the attachment between blastoderm and vitelline envelope impact gastrulation in insects — •Stefan Münster1,2,3, Alexander Mietke2,3, Akanksha Jain1, Pavel Tomancak1, and Stephan Grill1,2 — 1MPI-CBG, Dresden — 2TU Dresden, Biotec — 3MPI-PKS, Dresden
Gastrulation is a critical step during the development of multicellular organisms in which a single-layered tissue folds into a multi-layered germband. This shape change is characterized by tissue folding and large-scale tissue flow. The myosin-dependent forces that underlie this process have been increasingly investigated; however, thus far, the possible interaction between the moving tissue and the rigid shell surrounding the embryo has been neglected. Here, we present our quantitative findings on the physical mechanisms governing gastrulation in the red flour beetle, Tribolium castaneum. We investigated the forces expected within the tissue given the myosin distribution observed by multi-view light-sheet microscopy and discovered that an additional external force must be counteracting this tissue-intrinsic contractility. We then identified that a specific part of the tissue tightly adheres to the outer rigid shell. This attachment is mediated by a specific integrin whose knock-down leads to a complete loss of the counter-force. Moreover, in the fruit fly Drosophila melanogaster, knock-down of another integrin leads to a severe twist of the germband, suggesting that the integrin-mediated interaction between tissue and vitelline envelope may be conserved in insects.