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Tissue Determination Using the Animal Cap Transplant (ACT) Assay in Xenopus laevis
Published on: May 16, 2010
Tissue-specific developmental expression of OAX, a Xenopus repetitive element
K L Whitford1, J A Oakes, J Scholnick
1Department of Biology, College of William and Mary, Williamsburg, VA 23187-8795, USA.
Mechanisms of Development
|June 8, 2000
Summary
The Oocyte Activation in Xenopus (OAX) gene, a repetitive DNA element, is dynamically expressed during Xenopus embryogenesis. Its expression is tightly regulated in specific tissues during gastrula and tailbud stages.
Area of Science:
- Developmental Biology
- Genomics
- Molecular Biology
Background:
- The Xenopus laevis genome contains approximately 1% highly repetitive DNA, known as OAX, Satellite I, or Repetitive HindIII Monomer 2.
- OAX consists of tandemly repeated units of ~750 base pairs and encodes small RNAs transcribed by RNA polymerase III.
- Previous reports on OAX expression in early embryonic gene regulation are contradictory and incomplete.
Purpose of the Study:
- To comprehensively examine the expression pattern of OAX in Xenopus embryos.
- To clarify the spatial and temporal regulation of OAX during embryonic development.
Main Methods:
- Whole-mount in situ hybridization was employed to visualize OAX expression.
- RNase protection assays were utilized to quantify OAX expression levels.
Main Results:
- OAX expression initiates during Xenopus gastrula stages.
- By tailbud stages, distinct OAX expression zones were observed in the cement gland, somites, skeletal muscle, and neural tube.
- These findings indicate dynamic and regulated OAX gene expression.
Conclusions:
- OAX exhibits a dynamic expression pattern during Xenopus embryogenesis.
- Expression of OAX is under strict spatial and temporal control.
- This study provides a detailed map of OAX expression in developing Xenopus embryos.
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