Changes in calcium homeostasis and gene expression implicated in epilepsy in hippocampi of mice overexpressing ORAI1

We showed that the overexpression of ORAI1 in the neurons of murine brain leads to spontaneous occurrence of seizure-like events in aged animals. We aimed to identify the mechanism responsible for this phenomenon. Using modified Ca2+-addback assay in the slices of CA1 hippocampal region and FURA-2AM calcium indicator we found that overexpression of ORAI1 in neurons leads to altered Ca2+ response. Next, by RNASeq we identified set of genes, whose expression was changed in FVB/NJ-Tg(ORAI1)Ibd mice. Overall design: We isolated total RNA from hippocampi of wild-type (n=3) and of FVB/NJ-Tg(Orai1)Ibd (n=3) females and performed RNAseq experiments.

本研究证实，在小鼠脑神经元中过表达ORAI1，可使老龄动物自发出现癫痫样发作事件。本研究旨在阐明该现象的潜在分子机制。本研究采用改良的钙回流测定法（Ca2+-addback assay），以海马CA1区脑片为实验材料，结合FURA-2AM钙指示剂开展检测，发现神经元过表达ORAI1会导致钙信号响应异常。随后，本研究通过RNA测序（RNASeq），在FVB/NJ-Tg(ORAI1)Ibd小鼠中筛选得到一批差异表达基因。实验整体设计：本研究从野生型（n=3）与FVB/NJ-Tg(Orai1)Ibd（n=3）雌性小鼠的海马组织中提取总RNA，并完成RNA测序实验。