Wnt affects symmetry and morphogenesis during post-embryonic development in colonial chordates

Area of Science:

• Developmental Biology
• Regenerative Biology
• Cell Signaling

Background:

• Wnt signaling is a conserved pathway crucial for body axis establishment in development and regeneration.
• In Botryllus schlosseri, regeneration via blastogenesis bypasses embryonic stages.
• Wnt pathway modulation can lead to abnormal body axis phenotypes.

Purpose of the Study:

• To investigate the role of the canonical Wnt pathway in early asexual development (blastogenesis) in Botryllus schlosseri.
• To characterize the expression of specific Wnt ligands during this process.

Main Methods:

• In situ hybridization to analyze Wnt ligand expression (Wnt2B, Wnt5A, Wnt9A).
• Quantitative reverse transcription PCR (qRT-PCR) for gene expression analysis.
• Chemical manipulation of the Wnt pathway to observe effects on budding.

Main Results:

• Identified expression patterns of Wnt2B, Wnt5A, and Wnt9A during asexual development.
• Chemical Wnt pathway manipulation caused duplicated anterior/posterior axes and supernumerary budding.
• Observed loss of apical-basal cell polarity following Wnt pathway disruption.

Conclusions:

• Wnt signaling is essential for patterning during asexual development in Botryllus schlosseri.
• These findings suggest conserved Wnt-mediated patterning mechanisms across embryonic and regenerative development.
• Morphogenesis regulation by Wnt signaling is independent of developmental context (embryonic vs. regenerative).