Germ cells of many animals exhibit characteristic cytoplasmic structures— termed germ granules or nuage—which are ribonucleoprotein (RNP) amorphous aggregates without limiting membranes and are often closely associated with nuclei or mitochondria [1]. In several model animals, such as Drosophila, Caenorhabditis elegans, and Xenopus, studies on germ granules have mainly focused on their asymmetr...