The Autism‐Related lncRNA MSNP1AS Regulates Moesin Protein to Influence the RhoA, Rac1, and PI3K/Akt Pathways and Regulate the Structure and Survival of Neurons

Autism spectrum disorder (ASD) is a complex disease involving multiple genes and multiple sites, and it is closely related to environmental factors. It has been gradually revealed that long noncoding RNAs (lncRNAs) may regulate the pathogenesis of ASD at the epigenetic level. In neuronal cells, the lncRNA moesin pseudogene 1 antisense (MSNP1AS) forms a double‐stranded RNA with moesin (MSN) to suppress moesin protein expression. MSNP1AS overexpression can activate the RhoA pathway and inhibit the Rac1 and PI3K/Akt pathways; however, the regulation of Rac1 by MSNP1AS is not associated with MSN, and the effect on the RhoA pathway may also be associated with other factors. MSNP1AS can decrease the number and length of neurites, inhibit neuronal cell viability and migration, and promote apoptosis. Downregulation of MSN expression functions similarly to MSNP1AS, and its overexpression can block the above functions of MSNP1AS. In addition, in vivo experiments show that MSN improves social interactions and reduces repetitive behaviors in BTBR mice, decreases the activity of RhoA and restores the activity of PI3K/Akt pathway. Therefore, the abnormal expression of MSNP1AS in ASD patients might influence the structure and survival of neuronal cells through the regulation of moesin protein expression to facilitate the development and progression of ASD. These findings provide new evidence for studying the mechanisms of lncRNAs in ASD. Lay Summary Autism spectrum disorder (ASD) is a common neurodevelopmental disease and its neurodevelopmental mechanisms have not been elucidated. More and more studies have found that long noncoding RNAs (lncRNAs) can regulate the development of central nervous system in many ways and affect the pathogenic process of ASD. Moesin pseudogene 1 antisense (MSNP1AS) is an up‐regulated lncRNA in ASD patients. In‐depth functional experiments showed that MSNP1AS inhibited moesin protein expression and regulated the activation of multiple signaling pathways, thus decreasing the number and length of neurites, inhibiting neuronal cell viability and migration, and promoting apoptosis. Therefore, MSNP1AS is an important lncRNA related to ASD and can regulate the biological function of neurons.