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Published on: January 26, 2013
Activin-like factor from a Xenopus laevis cell line responsible for mesoderm induction
A J van den Eijnden-Van Raaij1, E J van Zoelent, K van Nimmen
1Hubrecht Laboratory, Netherlands Institute for Developmental Biology, Utrecht.
Nature
|June 21, 1990
Summary
Xenopus laevis ectoderm explants can be induced to form mesoderm using growth factors. Researchers identified that Xenopus laevis mesoderm-inducing factor (MIF) from XTC cells is the homologue of mammalian activin.
Area of Science:
- Developmental Biology
- Cell Biology
- Molecular Biology
Background:
- Mesoderm induction in amphibian embryogenesis is crucial for development.
- Growth factors like transforming growth factor-beta (TGF-beta) can mimic this process in vitro.
- The specific mesoderm-inducing factor (MIF) from Xenopus laevis XTC cells remains unidentified, despite showing TGF-beta-like properties.
Purpose of the Study:
- To investigate the nature of the mesoderm-inducing factor (MIF) produced by Xenopus laevis XTC cells.
- To analyze the relationship between MIF activity and activin activity in XTC cell clones.
- To determine if XTC-MIF is the Xenopus homologue of mammalian activin.
Main Methods:
- Isolation of homogeneous cell lines from heterogeneous XTC cell populations.
- Assaying for mesoderm-inducing factor (MIF) production in different XTC clones.
- Measuring transforming growth factor-beta (TGF-beta) activity and activin-like activity in cell extracts.
- Comparing MIF activity with activin activity across XTC cell lines.
Main Results:
- Only one XTC clone, XTC-GTX-11, produced significant MIF activity.
- This clone showed similar production of known growth factors, including TGF-beta activity, compared to other clones.
- A clear and consistent correlation was observed between the presence of MIF activity and activin activity in XTC cells and their clones.
- Activin A was identified as a potent mesoderm-inducing factor.
Conclusions:
- The mesoderm-inducing factor (MIF) from Xenopus laevis XTC cells is strongly associated with activin activity.
- XTC-MIF is identified as the Xenopus homologue of mammalian activin.
- This finding clarifies the molecular basis of mesoderm induction in Xenopus laevis embryogenesis.
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