Abstract
GERM PLASM COMPONENTS XDAZL, XCAT2, AND DEADSouth ARE REQUIRED FOR PRIMORDIAL GERM CELL FORMATION IN XENOPUS
Developmental biology, Vol.222(1), p.224
06/01/2000
DOI: 10.1016/S0012-1606(00)80002-0
Abstract
The inheritance of germ plasm, a specialized cytoplasm containing unique electron dense granules and localized RNAs, is believed to be required for primordial germ cell formation in Xenopus. However, no direct evidence for this has ever been obtained. Xdaz1, Xcat2, and DEADSouth are all RNA maternal components of Xenopus germ plasm and encode RNA-binding proteins. All are translationally repressed during oogenesis and not expressed until blastula stages. To determine the function of these germ plasm components, loss-of-function "mutants" were generated by depleting RNAs with antisense oligonucleotides (oligos) or by over-expressing mutant proteins. As suggested from their germ plasm localization, we show that all three are critically involved in PGC development. In preliminary experiments, over-expression of point mutants of Xdaz1, Xcat2 and DEADSouth that disrupt RNA binding result in the depletion or complete loss of PGCs in tadpoles. We further characterized Xdaz1, expressed in the germ plasm from blastula to early tailbud stages. Specific depletion of maternal Xdaz1 RNA results in tadpoles lacking, or severely deficient in, primordial germ cells (PGCs). In the absence of Xdaz1, PGCs do not successfully migrate from the ventral to the dorsal endoderm and do not reach the dorsal mesentery. Germ plasm aggregation and intracellular movements are normal indicating that the defect occurs after PGC formation. We propose that Xdaz1 is required for early PGC differentiation and is indirectly necessary for the migration of PGCs through the endoderm. As an RNA-binding protein, Xdaz1 may regulate translation or expression of factors that mediate migration of PGCs. Supported by NIH grant GM33932 to MLK.
Details
- Title: Subtitle
- GERM PLASM COMPONENTS XDAZL, XCAT2, AND DEADSouth ARE REQUIRED FOR PRIMORDIAL GERM CELL FORMATION IN XENOPUS
- Creators
- Mary Lou KingDouglas W HoustonMarialejandra Mora
- Resource Type
- Abstract
- Publication Details
- Developmental biology, Vol.222(1), p.224
- Publisher
- Elsevier B.V
- DOI
- 10.1016/S0012-1606(00)80002-0
- ISSN
- 0012-1606
- eISSN
- 1095-564X
- Language
- English
- Date published
- 06/01/2000
- Description audience
- Academic
- Academic Unit
- Biology
- Record Identifier
- 9984221496702771
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