Conserved gene regulatory module specifies lateral neural borders across bilaterians

Area of Science:

• Developmental Biology
• Evolutionary Biology
• Neuroscience

Background:

• The lateral neural plate border (NPB) in vertebrates contains central nervous system (CNS) and peripheral nervous system (PNS) progenitors.
• Invertebrates also exhibit PNS progenitors adjacent to the CNS lateral boundary.
• Conserved molecular mechanisms governing these lateral neural borders across species remain largely unknown.

Purpose of the Study:

• To investigate conserved molecular mechanisms specifying the lateral neural border in invertebrates.
• To compare these mechanisms with those in vertebrates.
• To identify novel genes involved in lateral neural border development.

Main Methods:

• Single-cell-resolution gene-expression profiling in *Caenorhabditis elegans*.
• Genetic analysis in *C. elegans*, *Drosophila melanogaster*, and *Ciona intestinalis*.
• Comparative analysis with *Xenopus laevis*.

Main Results:

• Orthologs of the vertebrate NPB specification module, including *Msx/vab-15*, *Pax3/7/pax-3*, and *Zic/ref-2*, are enriched in invertebrate lateral neuroblasts.
• *Msx/vab-15* specifies lateral neuroblasts in *C. elegans*, similar to its role in vertebrates.
• This module regulates mechanosensory neuron development in multiple invertebrate species.
• A novel specifier, *ZNF703/tlp-1*, functions with *Msx/vab-15* in both *C. elegans* and *Xenopus laevis*.

Conclusions:

• The molecular mechanisms specifying the lateral neural border are conserved across bilaterians.
• This suggests a common evolutionary origin for these developmental processes.
• Identified genes provide new insights into neural border development and evolution.