From: The function and regulation of vasa-like genes in germ-cell development
Species | Gene | RNA expression | RNA localization | Protein expression | Protein localization | Function | References |
---|---|---|---|---|---|---|---|
Fruit fly (Drosophila melanogaster) | vasa | Early embryo: uniform, followed by specific expression in germ cells. Ovary: uniform in nurse cells and oocyte. Testis: early stage spermatocytes and germline stem cells. | No | Germ cells: as soon as they form and throughout embryonic development. Ovary: germline stem cells, nurse cells, oocytes. Testis: early stages of spermatogenesis. | Oocyte and cleavage-stage embryos: in polar granules, nuclear bodies and dense cytoplasmic masses. | Early embryogenesis: abdomen development, nanos mRNA translation, formation of pole plasm and germ cells. Oogenesis: germline cyst development, oocyte differentiation, gurken mRNA translation, oocyte polarity, translation of oskar mRNA. | |
Mouse (Mus musculus) | Mvh | Testis: spermatocytes and early spermatids. Ovary: ND | No | Germ cells: as they arrive at thethe genital ridge. Ovary: early stages of oogenesis. Decreases during maturation. Not detected in mature oocytes. Testis: in spermatogonium to round spermatid stages. | Granules near nucleus in pachytene-diplotene spermatocytes. After meiosis: a large perinuclear granule up to spermatid nucleus elongation. Sperm: corresponds to that of the 'chromatoid body'. | Testis: required in PGCs during premeiotic stages of spermatogenesis for sperm differentiation before pachytene spermatocyte stage. Male mutants: PGC proliferation defects. Female mutants: fertile and show no defects of oogenesis. | |
Zebrafish (Danio rerio) | vasa | Maternally supplied to embryo. From the 32-cell stage, detected in four blastomeres. Gastrulation: expressed in four PGC clusters as they migrate towards the gonad. Testis: spermatogenesis, excluding mature spermatozoa. Ovary: all stages of oogenesis. | One-cell embryo: ring between yolk and cytoplasm. Two- to four-cell embryo: near cleavage furrow, inherited by four cells. Then asymmetrically localized and distributed between dividing blastomeres until late blastula, when it fills PGCs' cytoplasm. Late oogenesis: oocyte cortex. | Maternal protein uniformly distributed during blastula stages. At late blastula, distinct expression in PGCs as expression in somatic cells decreases. | Associated with germinal vesicle in early oogenesis. From late blastula on, associated with nuclear envelope in a pattern distinct from that of the RNA. | ND | |
Planarian (Dugesia japonica) | DjvlgA, DjvlgB | Testis: DjvlgA in spermatogonia, spermatocytes, spermatids. DjvlgB only in spermatocytes. Ovary: both expressed in oocytes. Outside gonad DjvlgA expressed in totipotent neoblasts. | No | ND | ND | ND | [26] |
Frog (Xenopus laevis) | XVLG1 | Gonad in both sexes. Ovary: all stages of oogenesis. Gastrulation: PGC-specific expression. | No | Oocytes and unfertilized eggs. Blastula and gastrula: all cells, intensity of staining decreasing with time. After gastrulation: level increases in PGCs. | Embryos: appears to be perinuclear. | Â | |
Chick (Gallus gallus) | Cvh | Testis: spermatogonia to mature spermatocytes. Ovary: ND | ND | Embryos: maternal protein from the one-cell stage. Before gastrulation: Cvh-positive PGCs in center of area pellucida. Migrating and post-migratory PGCs. Testis: spermatogonia to round spermatids. Ovary: immature oocytes. | Cleaving embryos: basal part of cleavage furrows.Testis: granular staining in spermatocytes. Ovary: underneath plasma membrane, near germ-plasm-associated organelles and molecules such as mitochondria and spectrin. | ND | [8] |
Ascidian (Ciona intestinalis) | Ci-DEAD1 | Embryo: mesenchymal cells and posterior cells presumed to be germ cells. Ovary: early oogonic cells. Testis: early spermatogenic cells. | Early embryos: posterior during two- to four-cell stage, inherited by presumed germ cells. | ND | ND | ND | [27] |
Nematode (Caenorhabditis elegans) | glh-1,glh-2, glh-3,glh-4 | glh-1, glh-2, glh-3 and glh-4 expressed in all cells of early cleavage stages followed by a decrease to background levels. All expressed in germline cells in male and hermaphrodite. | No | All expressed throughout life, first in germline blastomeres and later in germ cells in gonad. | All localized to P-granules that segregate to germline blastomeres. Granules are cytoplasmic in oocyte and early embryo and perinuclear at later stages. | G1h-1, g1h-2 and g1h-4 products are required for germ-cell proliferation and gametogenesis. Oogenesis and spermatogenesis defective in glh-1/4(RNAi), with many cells not proceeding beyond pachytene. | |
Human (Homo sapiens) | VASA | In the fetus and adult, gonad-specific expression in both sexes. | ND | Germ cells: expressed in PGCs as they populate the gonadal ridge as well as in PGCs that have not yet reached this target. Testis: spermatogonia, spermatocysts and spermatids. Ovary: oocytes. | Testis: granular staining in spermatocytes. Ovary: in fetal oocytes: within a compact perinuclear body. In adult oocytes no subcellular localization. | ND: hereditary infertility syndromes that map to the chromosomal region of VASA have not yet been found. | [30] |