Function and regulation of FoxF1 during Xenopus gut development

Area of Science:

• Developmental Biology
• Molecular Genetics
• Organogenesis

Background:

• Visceral mesoderm development is essential for gut organogenesis.
• Understanding genes regulating visceral mesoderm is key to understanding gut development.
• FoxF1 is a gene expressed in lateral plate and visceral mesoderm.

Purpose of the Study:

• To elucidate the function and regulation of FoxF1 in Xenopus gut development.
• To investigate the role of FoxF1 in visceral mesoderm proliferation and differentiation.
• To explore the molecular mechanisms upstream of FoxF1, including BMP4 signaling.

Main Methods:

• Injected FoxF1 morpholino into Xenopus embryos to observe gut development.
• Assessed expression of visceral mesoderm differentiation markers (Xbap, alpha-smooth muscle actin).
• Analyzed FoxF1 regulation by BMP4 signaling in animal cap assays.
• Created transgenic Xenopus tadpoles using cis-regulatory elements of FoxF1 to drive GFP expression.

Main Results:

• FoxF1 morphants exhibited abnormal gut development, including impaired mesoderm proliferation and differentiation.
• Key markers of visceral mesoderm differentiation were not activated in FoxF1-deficient embryos.
• FoxF1 is a downstream target of BMP4 signaling; FoxF1 overexpression rescued BMP4-deficient phenotypes.
• A 2 kb upstream DNA fragment of FoxF1 drove specific temporal-spatial GFP expression in transgenic Xenopus.

Conclusions:

• FoxF1 is essential for proper visceral mesoderm development and gut organogenesis in Xenopus.
• FoxF1 plays a critical role in the proliferation and differentiation of lateral plate and visceral mesoderm.
• The identified cis-regulatory elements of FoxF1 offer a tool for targeted gene expression in the lateral plate mesoderm.