The Balbiani Body and Germ Cell Determinants: 150 Years Later

Mouse oocytes within germ cell cysts and primordial follicles contain a Balbiani body

“…To look for a mouse Balbiani body, we focused on cyst-stage germ cells and on newly forming primordial follicles, the stages where Balbiani bodies can first be observed in Drosophila and Xenopus ovaries (23). Using electron microscopy, we observed that Golgi stacks are arranged in a distinctive circular manner in young mouse oocytes ( Fig.…”

“…The presence of a Balbiani body in diverse species of young oocytes suggests that it is associated with a conserved function. The strongest candidate for such a role is in the transport and localization of organelles and RNAs within oocytes (23). Consequently, we examined whether conserved proteins known to function in these processes within oocytes of other species are present in the mouse Balbiani body.…”

“…The mouse chromatoid body contains the me31B homolog, Ddx25, which is essential for male fertility and has been implicated in translational regulation (18). Other components of the chromatoid body include Vasa and Tudor proteins (19,20) The Balbiani body or mitochondrial cloud is a collection of organelles asymmetrically located adjacent to the nucleus in very young oocytes of diverse species (21)(22)(23). Balbiani bodies contain mitochondria, ER, and granulofibrillar material (GFM) organized in a characteristic manner.…”

Pluripotent Gametogenic Stem Cells of Asexually Reproducing Invertebrates

“…The specific electron-dense material of germinal granules was denoted in the early XX century by the German terms Keimbahnchromidien and Keimbahnplasma, and this terminology was directly related to Weismann's; later the English terms germ plasm, germ cell determinants, polar, perinuclear, chromatoid, germinal, germ granules (bodies), dense bodies, ectosomes, the French term nuage, and many others were introduced (see Mahowald, 1971Mahowald, , 2001Beams & Kessel, 1974;Eddy, 1975;Ikenishi, 1998;Houston & King, 2000;Isaeva & Reunov, 2001;Matova & Cooley, 2001;Seydoux & Braun, 2006;Lim and Kai, 2007;Strome & Lehnam, 2007;Isaeva et al, 2008bIsaeva et al, , 2009Frank et al, 2009;Isaeva, 2010). Complex structures, including electron-dense material and mitochondria in vitellogenic oocytes, are called also the Balbiani body, vitelline (yolk) body, mitochondrial cloud, intermitochondrial cement, yolk nucleus: "the chaos in the nomenclature" complicates the comparison of these structures in different species (Kloc et al, 2004). The presence of germinal (perinuclear) granules is an evolutionary conserved feature of germline cells in multicellular animals.…”

Teachings from the egg: New and unexpected functions of RNAs

“…An animal egg is an extraordinary cell that combines all housekeeping functions and organelles of a somatic cell with the set of unique functions and wondrous organelles designed exclusively to support reproduction and the development of future embryo (de Smedt et al, 2000;Kloc et al, 2004). These properties of egg cells allow for discoveries and insights that are impossible or hard to achieve by studying somatic cells.…”