title: Smaug variants in neural and non-neuronal cells.
abstract: Mammalian Smaug1/Samd4a is an mRNA regulator involved in synapse plasticity and additional non-neuronal functions. Here we analyzed the expression of Smaug1/Samd4a variants and Smaug2/Samd4b in primary hippocampal neurons and non-neuronal cell lines. We found that multiple Smaug proteins are present in several mammalian cell lines, including a canonical full length Smaug1, a Smaug1 variant that lacks the third exon, termed ΔEIII, and Smaug2, the product of a highly homologous gene. These three major isoforms are expressed differentially along neuron development and form cytosolic bodies when transfected in cell lines. By using luciferase reporters, we found that the ΔEIII isoform, which lacks 10 amino acids in the sterile α motif involved in RNA binding, shows a RNA-binding capacity and repressor activity comparable to that of the full length Smaug1. These observations are an important groundwork for molecular studies of the Smaug post-transcriptional pathway, which is relevant to neuron development, mitochondrial function and muscle physiology in health and disease.
authors.affiliation: Fundación Instituto Leloir, Buenos Aires, Argentina; Instituto de Investigaciones Bioquímicas Buenos Aires-Consejo Nacional de Investigaciones Científicas y Tecnológicas, Buenos Aires, Argentina.
authors.forename: Ana Julia
authors.initials: AJ
authors.lastname: Fernández-Alvarez
authors.affiliation: Fundación Instituto Leloir, Buenos Aires, Argentina; Instituto de Investigaciones Bioquímicas Buenos Aires-Consejo Nacional de Investigaciones Científicas y Tecnológicas, Buenos Aires, Argentina; Facultad de Ciencias Exactas y Naturales, University of Buenos Aires, Buenos Aires, Argentina.
authors.forename: Malena Lucía
authors.initials: ML
authors.lastname: Pascual
authors.affiliation: Fundación Instituto Leloir, Buenos Aires, Argentina; Instituto de Investigaciones Bioquímicas Buenos Aires-Consejo Nacional de Investigaciones Científicas y Tecnológicas, Buenos Aires, Argentina; Facultad de Ciencias Exactas y Naturales, University of Buenos Aires, Buenos Aires, Argentina.
authors.forename: Graciela Lidia
authors.initials: GL
authors.lastname: Boccaccio
authors.affiliation: Fundación Instituto Leloir, Buenos Aires, Argentina; Instituto de Investigaciones Bioquímicas Buenos Aires-Consejo Nacional de Investigaciones Científicas y Tecnológicas, Buenos Aires, Argentina.
authors.forename: María Gabriela
authors.initials: MG
authors.lastname: Thomas
keywords: mRNA silencing; muscular dystrophy; processing bodies; stress granules; synaptogenesis; translation