TY - JOUR AB - Germ granules, condensates of phase-separated RNA and protein, are organelles that are essential for germline development in different organisms. The patterning of the granules and their relevance for germ cell fate are not fully understood. Combining three-dimensional in vivo structural and functional analyses, we study the dynamic spatial organization of molecules within zebrafish germ granules. We find that the localization of RNA molecules to the periphery of the granules, where ribosomes are localized, depends on translational activity at this location. In addition, we find that the vertebrate-specific Dead end (Dnd1) protein is essential for nanos3 RNA localization at the condensates’ periphery. Accordingly, in the absence of Dnd1, or when translation is inhibited, nanos3 RNA translocates into the granule interior, away from the ribosomes, a process that is correlated with the loss of germ cell fate. These findings highlight the relevance of sub-granule compartmentalization for post-transcriptional control and its importance for preserving germ cell totipotency. AU - Westerich, Kim Joana AU - Tarbashevich, Katsiaryna AU - Schick, Jan AU - Gupta, Antra AU - Zhu, Mingzhao AU - Hull, Kenneth AU - Romo, Daniel AU - Zeuschner, Dagmar AU - Goudarzi, Mohammad AU - Gross-Thebing, Theresa AU - Raz, Erez ID - 14781 IS - 17 JF - Developmental Cell KW - Developmental Biology KW - Cell Biology KW - General Biochemistry KW - Genetics and Molecular Biology KW - Molecular Biology SN - 1534-5807 TI - Spatial organization and function of RNA molecules within phase-separated condensates in zebrafish are controlled by Dnd1 VL - 58 ER - TY - JOUR AB - Blebs are cellular protrusions observed in migrating cells and in cells undergoing spreading, cytokinesis, and apoptosis. Here we investigate the flow of cytoplasm during bleb formation and the concurrent changes in cell volume using zebrafish primordial germ cells (PGCs) as an in vivo model. We show that bleb inflation occurs concomitantly with cytoplasmic inflow into it and that during this process the total cell volume does not change. We thus show that bleb formation in primordial germ cells results primarily from redistribution of material within the cell rather than being driven by flow of water from an external source. AU - Goudarzi, Mohammad AU - Boquet-Pujadas, Aleix AU - Olivo-Marin, Jean Christophe AU - Raz, Erez ID - 6093 IS - 2 JF - PLOS ONE TI - Fluid dynamics during bleb formation in migrating cells in vivo VL - 14 ER -