Unravelling the evolutionary origin, architecture, development and regulation of neuromuscular systems

Introduction

Muscles and neurons are a major hallmark of animals, and given their impact on the organisms’ motility, the emergence of an interacting neuro-muscular system has tremendously shaped the evolution of animal body plans and behavioral repertoire. Neurons and muscle cells closely interact and likely have co-evolved.

Research Gap

Yet, the evolutionary origin of different neuronal and muscular cell types remains elusive, mainly due to a lack of thorough studies in basal metazoans.

Project Aims

In this project, I aim to unravel the evolutionary origin, architecture, regulation, and systemic properties of the neuro-muscular system by:

1. A broad comparative approach among non-bilaterians.
2. A deeper functional dissection in two model cnidarians:
   • The sea anemone Nematostella vectensis
   • The hydrozoan Clytia hemisphaerica.

Methodology

By comparing single cell transcriptomes, we will reveal common or distinct molecular profiles of neurons and muscles in early branching, non-bilaterian species (i.e., Porifera, Ctenophora, Cnidaria) and bilaterians (i.e., all other animals). This will allow us to identify:

• Ancestral versus independently evolved neuro-muscular modules comprised of specifically interacting cells.

We will then use genome editing, transgenics, and newly developed functional tools to unravel:

• The architecture of the cnidarian neuro-muscular system on single cell resolution.
• The function of specific neuronal and muscle populations.
• Their plasticity and regenerative capacity.

Hypothesis

We hypothesize to identify common cellular network modules allowing for fast and slow neuro-muscular regulation in bilaterians and non-bilaterians, which may be ancestral or convergently evolved in different animal lineages.

Expected Outcomes

The expected outcome will impact our understanding of the evolution of organisms with complex body plans.