ANALYSIS OF THE EXPRESSION AND MODULATION OF THE HSA-MIR-216/217 CLUSTER IN HUMAN PLURIPOTENT STEM CELLS AND ITS DIFFERENTIATED NEURAL PROGENY

RODRÍGUEZ VARELA, MARÍA SOLEDAD; FERRIOL LAFFOUILLERE, SOFÍA LUJÁN; MUCCI, SOFÍA; ISAJA, LUCIANA; SEVLEVER, GUSTAVO EMILIO; SCASSA, MARÍA ELIDA; ROMORINI, LEONARDO

Mar del Plata

Congreso; REUNIÓN CONJUNTA SAIC SAI&FAIC SAFIS 2022; 2022

SAIC SAI&FAIC SAFIS

Human pluripotent stem cells (hPSCs) have the potential to differen- tiate into a wide range of specialized cells. MicroRNAs (miRNAs) are post-transcriptional regulators of gene expression that have been shown to be required for key biological processes such as differenti- ation. Many of them have been described as key regulators through- out neural development. However, knowledge on miRNA-based regulation during neuronal differentiation from hPSCs is still at its dawn. We have previously identified by RNA-Seq that the hsa- miR-216/217 cluster is highly expressed in hPSCs-derived neural stem cells (NSC) and neurons (NEU), without measurable expres- sion levels in hPSCs. Given this expression profile, we aim to study the role of this cluster in hPSCs and its differentiated neural progeny. In silico target genes and gene ontology analysis suggested that this cluster may regulate genes involved in NSC and NEU proliferation. By modulating the expression levels of miR-217-5p in hPSCs and NSC with exogenous molecules (mimic/inhibitors), we found that over-expression of miR-217-5p in hPSCs increased the percentage of G1 phase population. In contrast, we did not observe differenc- es in the cell cycle distribution in NSC-transfected with exogenous molecules that inhibit or overexpress miR-217-5p. Additionally, by a cell viability assay, we determined that miR-217-5p induction did not affect hPSCs viability. Finally, we analyzed by RT-qPCR the expres- sion levels of putative miR-216/217 cluster target genes (WEE1, RREB1, COL4A4, ANLN, GRIA3, SIRT1 and CYCLIN D1). We observed that miR-217-5p over-expression decreased OCT-4 and GRIA3 mRNA expression levels in human embryonic stem cells and WEE1, SIRT1 and CYCLIN D1 mRNA expression levels in human induced pluripotent stem cells. Our results suggest that the upregu- lation of miR-217-5p accompanied by downregulation of genes gov- erning stemness and proliferation may participate in the regulation of the early neural specification of hPSCs.