In silico Identification and Gene Network Analysis of Potential Novel MicroRNAs detected from Rat Hippocampal ESTs during Treadmill Running

Abstract

MicroRNAs (miRNAs) have been previously described to regulate gene expression. This activity was explored in silico to determine if miRNAs regulate gene expression in the brain as a consequence of physical exercise. Up-regulated and down-regulated genes in the form of Expressed Sequence Tags (ESTs) were identified from hippocampuses of rats (Rattus norvegicus) subjected to treadmill running. After homology search and secondary structure prediction, we found three new potential rat miRNAs, one similar to minu-miR-574-5p and two similar to rno-miR-297. Their possible brain-specific target genes were predicted using miRBase Targets database. IPA-gencrated (Ingenuity Pathways Analysis) interactomcs of target genes showed their possible role in inducing neurogencsis and preventing Ca2' influxdependent nerve cell death and long term depression. These interactions can be mediated by the potential novel miRNAs. suggesting new insights on the effects of physical exercise in relation to learning, memory enhancement, and possible prevention of neurological illnesses like Lou Gehrig’s and Alzheimer’s disease.