David Beeson, MA, PhD, Department of Clinical Neurology, University of Oxford, Oxford, UK, discusses the difference between the mouse and human neuromuscular junction (NMJ) in terms of expression of adult and fetal forms of acetylcholine receptors (AChRs). The distinction between both is important because our current knowledge of the NMJ is through murine studies. However, the fetal and adult forms of the receptors differ in both species, and therefore our knowledge of the receptors in mice is not directly transferable to humans. For example, expression of fetal forms of the receptors ends 21 days after birth in mice, whereas there is a low-level expression of fetal forms of the receptors throughout adult human life. This low level of expression would be lethal in mice but is not in humans. By contrast, null mutations in the fetal form of the receptor that is lethal in mice can be found in humans but are not always fatal, and people born with these null mutations in the fetal form of the receptor can survive on only the adult form. This highlights the variability and plasticity of the different forms of the receptors in mice and humans and the different outcomes on survival in the respective species. This interview took place during the European Academy of Neurology 2021 congress.
