Nodal signalling and asymmetry of the nervous system.
The role of Nodal signalling in nervous system asymmetry is still poorly understood. Here, we review and discuss how asymmetric Nodal signalling controls the ontogeny of nervous system asymmetry using a comparative developmental perspective. A detailed analysis of asymmetry in ascidians and fishes reveals a critical context-dependency of Nodal function and emphasizes that bilaterally paired and midline-unpaired structures/organs behave as different entities. We propose a conceptual framework to dissect the developmental function of Nodal as asymmetry inducer and laterality modulator in the nervous system, which can be used to study other types of body and visceral organ asymmetries. Using insights from developmental biology, we also present novel evolutionary hypotheses on how Nodal led the evolution of directional asymmetry in the brain, with a particular focus on the epithalamus. We intend this paper to provide a synthesis on how Nodal signalling controls left-right asymmetry of the nervous system.This article is part of the themed issue 'Provocative questions in left-right asymmetry'.
Anatomy and Developmental Biology, Institute of Biomedical Sciences, Faculty of Medicine, Universidad de Chile, PO Box 70031, Santiago, Chile.|Biomedical Neuroscience Institute, Independencia 1027, Santiago, Chile.
Iskra A
IA
Signore
Anatomy and Developmental Biology, Institute of Biomedical Sciences, Faculty of Medicine, Universidad de Chile, PO Box 70031, Santiago, Chile.|Biomedical Neuroscience Institute, Independencia 1027, Santiago, Chile.
Karina
K
Palma
Anatomy and Developmental Biology, Institute of Biomedical Sciences, Faculty of Medicine, Universidad de Chile, PO Box 70031, Santiago, Chile mconcha@med.uchile.cl.|Biomedical Neuroscience Institute, Independencia 1027, Santiago, Chile.|Center for Geroscience, Brain Health and Metabolism, Santiago, Chile.
Miguel L
0000-0003-3353-9398
ML
Concha
D000818:Animals; D019521:Body Patterning; D018507:Gene Expression Regulation, Developmental; D007448:Invertebrates / Q000196:embryology / Q000235:genetics* / Q000254:growth & development; D055457:Nodal Protein / Q000235:genetics* / Q000378:metabolism; D015398:Signal Transduction; D014714:Vertebrates / Q000196:embryology / Q000235:genetics* / Q000254:growth & development
D055457:Nodal Protein
Nodal; asymmetry; context-dependency; epithalamus; evo-devo; nervous system