- ItemOpen AccessNeuregulin-1 is associated to postsynaptic sites contacting afferent C-type cholinergic terminals on lower motoneurons: changes in murine models of motoneuron diseases(2014) Gallart-Palau, Xavier; Tarabal Mostazo, Olga; Casanovas i Llorens, Anna; Sábado, Javier; Correa, Francisco; Cerveró Cebrià, Clàudia; Hereu, Marta; Piedrafita Llorens, Lídia; Calderó i Pardo, Jordi; Esquerda Colell, JosepPioneering ultrastructural studies have defined different types of synapses (F-, S- and C-type boutons) on lower motoneurons (MNs). C-Type boutons are large nerve terminals characteristic of somatic alpha-MNs and display a subsynaptic cistern adjacent to postsynaptic membrane. The cholinergic nature of C-terminals has been established, and their origin from local interneurons has been deciphered. In a recent study concerning neuregulin-1 (NRG-1) on phrenic MNs, it has been reported that this trophic factor is expressed in cholinergic terminals synapsing these MNs and a presynaptic localization of this protein was suggested. * NRG-1 is concentrated at the subsynaptic cysterns of alpha-MN afferent cholinergic C-terminals. * ALS-resistant MNs at the oculomotor nuclei show low NRG-1 expression. * NRG-1 is developmentally regulated and depends on the maintenance of nerve muscle interactions. * The transient increase in NRG-1-positive spots on MN somata during SMA or ALS progression is in concordance with the described sprouting of C-terminals in ALS.