Smaug variants in neural and non-neuronal cells

ANA JULIA FERNANDEZ ALVAREZ; GRACIELA LIDIA BOCCACCIO; MALENA LUCIA PASCUAL; MARIA GABRIELA THOMAS

Communicative & Integrative Biology

Taylor & Francis

Año: 2016 vol. 9 p. 1139251 - 1139252

Mammalian Smaug1/Samd4a is an mRNA regulator involved in synapse plasticity and additionalnon-neuronal functions. Here we analyzed the expression of Smaug1/Samd4a variants andSmaug2/Samd4b in primary hippocampal neurons and non-neuronal cell lines. We found thatmultiple Smaug proteins are present in several mammalian cell lines, including a canonical fulllength Smaug1, a Smaug1 variant that lacks the third exon, termed DEIII, and Smaug2, the productof a highly homologous gene. These three major isoforms are expressed differentially along neurondevelopment and form cytosolic bodies when transfected in cell lines. By using luciferase reporters,we found that the DEIII isoform, which lacks 10 amino acids in the sterile a motif involved in RNAbinding, shows a RNA-binding capacity and repressor activity comparable to that of the full lengthSmaug1. These observations are an important groundwork for molecular studies of the Smaug posttranscriptionalpathway, which is relevant to neuron development, mitochondrial function andmuscle physiology in health and disease.