@inbook{9245, abstract = {Tissue morphogenesis is driven by mechanical forces triggering cell movements and shape changes. Quantitatively measuring tension within tissues is of great importance for understanding the role of mechanical signals acting on the cell and tissue level during morphogenesis. Here we introduce laser ablation as a useful tool to probe tissue tension within the granulosa layer, an epithelial monolayer of somatic cells that surround the zebrafish female gamete during folliculogenesis. We describe in detail how to isolate follicles, mount samples, perform laser surgery, and analyze the data.}, author = {Xia, Peng and Heisenberg, Carl-Philipp J}, booktitle = {Germline Development in the Zebrafish}, editor = {Dosch, Roland}, isbn = {978-1-0716-0969-9}, issn = {1940-6029}, keywords = {Tissue tension, Morphogenesis, Laser ablation, Zebrafish folliculogenesis, Granulosa cells}, pages = {117--128}, publisher = {Humana}, title = {{Quantifying tissue tension in the granulosa layer after laser surgery}}, doi = {10.1007/978-1-0716-0970-5_10}, volume = {2218}, year = {2021}, } @article{8680, abstract = {Animal development entails the organization of specific cell types in space and time, and spatial patterns must form in a robust manner. In the zebrafish spinal cord, neural progenitors form stereotypic patterns despite noisy morphogen signaling and large-scale cellular rearrangements during morphogenesis and growth. By directly measuring adhesion forces and preferences for three types of endogenous neural progenitors, we provide evidence for the differential adhesion model in which differences in intercellular adhesion mediate cell sorting. Cell type–specific combinatorial expression of different classes of cadherins (N-cadherin, cadherin 11, and protocadherin 19) results in homotypic preference ex vivo and patterning robustness in vivo. Furthermore, the differential adhesion code is regulated by the sonic hedgehog morphogen gradient. We propose that robust patterning during tissue morphogenesis results from interplay between adhesion-based self-organization and morphogen-directed patterning.}, author = {Tsai, Tony Y.-C. and Sikora, Mateusz K and Xia, Peng and Colak-Champollion, Tugba and Knaut, Holger and Heisenberg, Carl-Philipp J and Megason, Sean G.}, issn = {1095-9203}, journal = {Science}, keywords = {Multidisciplinary}, number = {6512}, pages = {113--116}, publisher = {American Association for the Advancement of Science}, title = {{An adhesion code ensures robust pattern formation during tissue morphogenesis}}, doi = {10.1126/science.aba6637}, volume = {370}, year = {2020}, } @article{6087, abstract = {Cell fate specification by lateral inhibition typically involves contact signaling through the Delta-Notch signaling pathway. However, whether this is the only signaling mode mediating lateral inhibition remains unclear. Here we show that in zebrafish oogenesis, a group of cells within the granulosa cell layer at the oocyte animal pole acquire elevated levels of the transcriptional coactivator TAZ in their nuclei. One of these cells, the future micropyle precursor cell (MPC), accumulates increasingly high levels of nuclear TAZ and grows faster than its surrounding cells, mechanically compressing those cells, which ultimately lose TAZ from their nuclei. Strikingly, relieving neighbor-cell compression by MPC ablation or aspiration restores nuclear TAZ accumulation in neighboring cells, eventually leading to MPC re-specification from these cells. Conversely, MPC specification is defective in taz−/− follicles. These findings uncover a novel mode of lateral inhibition in cell fate specification based on mechanical signals controlling TAZ activity.}, author = {Xia, Peng and Gütl, Daniel J and Zheden, Vanessa and Heisenberg, Carl-Philipp J}, journal = {Cell}, number = {6}, pages = {1379--1392.e14}, publisher = {Elsevier}, title = {{Lateral inhibition in cell specification mediated by mechanical signals modulating TAZ activity}}, doi = {10.1016/j.cell.2019.01.019}, volume = {176}, year = {2019}, } @article{6899, abstract = {Intra-organ communication guides morphogenetic processes that are essential for an organ to carry out complex physiological functions. In the heart, the growth of the myocardium is tightly coupled to that of the endocardium, a specialized endothelial tissue that lines its interior. Several molecular pathways have been implicated in the communication between these tissues including secreted factors, components of the extracellular matrix, or proteins involved in cell-cell communication. Yet, it is unknown how the growth of the endocardium is coordinated with that of the myocardium. Here, we show that an increased expansion of the myocardial atrial chamber volume generates higher junctional forces within endocardial cells. This leads to biomechanical signaling involving VE-cadherin, triggering nuclear localization of the Hippo pathway transcriptional regulator Yap1 and endocardial proliferation. Our work suggests that the growth of the endocardium results from myocardial chamber volume expansion and ends when the tension on the tissue is relaxed.}, author = {Bornhorst, Dorothee and Xia, Peng and Nakajima, Hiroyuki and Dingare, Chaitanya and Herzog, Wiebke and Lecaudey, Virginie and Mochizuki, Naoki and Heisenberg, Carl-Philipp J and Yelon, Deborah and Abdelilah-Seyfried, Salim}, issn = {20411723}, journal = {Nature communications}, number = {1}, pages = {4113}, publisher = {Nature Publishing Group}, title = {{Biomechanical signaling within the developing zebrafish heart attunes endocardial growth to myocardial chamber dimensions}}, doi = {10.1038/s41467-019-12068-x}, volume = {10}, year = {2019}, }