Transcriptome analysis elucidates key developmental components of bryozoan lophophore development

Area of Science:

• Developmental Biology
• Evolutionary Biology
• Genomics

Background:

• The lophophore, a feeding structure, is a shared trait among Bryozoa (Ectoprocta), Brachiopoda, and Phoronida.
• Understanding lophophore development in Lophophorata offers insights into metazoan morphological evolution.

Purpose of the Study:

• To investigate the molecular mechanisms underlying lophophore development in the bryozoan Bugula neritina.
• To identify differentially expressed genes during larval metamorphosis and their role in lophophore formation.

Main Methods:

• Transcriptome profiling of Bugula neritina at swimming larval, early metamorphic, and late metamorphic stages using Illumina HiSeq2000.
• In situ hybridization of 23 genes involved in Wnt, BMP, Notch, and Hedgehog signaling pathways.

Main Results:

• Identified differential gene expression in development, immune response, and neurogenesis during metamorphosis.
• Revealed regulatory roles of Wnt, BMP, Notch, and Hedgehog pathway genes in lophophore and digestive tract development.
• Supported the hypothesis of pre-patterning of developmental precursors by differential gene expression.

Conclusions:

• The study provides a foundation for understanding the developmental divergence and convergence of lophophore precursors in Lophophorata.
• Findings contribute to a deeper understanding of the molecular basis of morphological trait formation in animals.