Presence of activin (erythroid differentiation factor) in unfertilized eggs and blastulae of Xenopus laevis.
AUTOR(ES)
Asashima, M
RESUMO
Activin A, a member of the transforming growth factor beta superfamily, has recently been found to have potent mesoderm-inducing activity on isolated early Xenopus animal-cap cells. We measured the activin activity of the Xenopus egg extract by using an erythroid-differentiating test with Friend leukemia cells. The results showed that an activin homologue is, indeed, contained in unfertilized eggs and blastulae of Xenopus laevis in a considerable amount. This activity was eluted at the same retention time as human activin A when fractionated by reversed-phase HPLC. Furthermore, the fraction containing erythroid-differentiating factor activity had mesoderm-inducing activity on Xenopus animal-cap cells. The mesoderm-inducing activity of this fraction was suppressed when coincubated with follistatin, an activin-binding protein. These results suggest that an endogenous activin may be a natural mesoderm-inducing factor acting in Xenopus embryogenesis.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=52115Documentos Relacionados
- Fidelity of transcription of Xenopus laevis globin genes injected into Xenopus laevis oocytes and unfertilized eggs.
- Inheritance of DNA methylation in microinjected eggs of Xenopus laevis.
- Purification of a DNA-binding protein from Xenopus laevis unfertilized eggs.
- Multiple forms of maturation-promoting factor in unfertilized Xenopus eggs.
- Replication of SV40 chromatin in extracts from eggs of Xenopus laevis.