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In Vitro Culture of Epithelial Cells from Different Anatomical Regions of the Human Amniotic Membrane
Published on: November 28, 2019
La racha primitiva amniótica está definida por la intercalación de células epiteliales antes de la gastrulación
Octavian Voiculescu1, Federica Bertocchini, Lewis Wolpert
1Department of Anatomy & Developmental Biology, University College London, Gower Street, London WC1E 6BT, UK. o.voiculescu@ucl.ac.uk
Nature
|October 12, 2007
Resumen
La formación de rayas primitivas de amniotas implica una nueva intercalación de células ectodérmicas antes de la gastrulación, guiada por el factor de crecimiento de los fibroblastos y la señalización Wnt. Este mecanismo posiciona la racha primitiva en la línea media, lo que difiere del desarrollo del anamniote.
Área de la Ciencia:
- Biología del desarrollo Biología del desarrollo.
- Biología celular Biología celular.
- Biología del desarrollo evolutivo Biología del desarrollo evolutivo
Sus antecedentes:
- La gastrulación establece las capas germinales (mesodermo, endodermo) desde el ectodermo.
- Las formas de mesendodermo amniótico (aves, mamíferos) se forman a través de la raya primitiva, precedida por movimientos de células ectodérmicas.
- Los mecanismos que controlan la formación de rayas primitivas de amniote siguen siendo en gran medida desconocidos.
Objetivo del estudio:
- Para dilucidar los mecanismos celulares y moleculares que rigen la formación de rayas primitivas en amniotas.
- Investigar el papel de la intercalación celular y las vías de señalización en el posicionamiento de la raya primitiva.
- Para comparar la formación de rayas primitivas de amniotas con los procesos de gastrulación en anamniotas.
Principales métodos:
- Microscopia de lapso de tiempo multifotónico de embriones de pollito (Gallus gallus).
- Análisis de la dinámica de la intercalación de las células ectodérmicas.
- Investigación de la participación del factor de crecimiento de los fibroblastos (FGF) y de la vía de polaridad celular plana (PCP) de Wnt.
Principales resultados:
- Una nueva intercalación celular medio-lateral ocurre en el ectodermo antes de la formación de rayas primitivas.
- Esta intercalación está dirigida por el factor de crecimiento del fibroblasto del hipoblasto, que regula los componentes de la vía Wnt.
- La interrupción de la señalización de Wnt conduce a la formación de mesendodermo periférico, a diferencia del desarrollo de rachas primitivas de la línea media.
Conclusiones:
- La racha primitiva amniótica probablemente evolucionó desde el blastóporo ancestral.
- Un evento adicional de intercalación medio-lateral pre-gastrulación coloca la racha primitiva amniótica en la línea media.
- Este mecanismo de intercalación específico del amniote opera independientemente de la formación del mesendodermo.
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