GSE208330
Detailed analysis of dorsal-ventral gradients of gene expression in the rat hippocampus
Dorsal and ventral parts of the hippocampus despite similar histological structure are known to be involved in performance of different functions. Previous studies using next generation sequencing showed that these two hippocampal parts differ in the expression of many genes, however, stability of dorsoventral gradient of gene expression remains open question. Here, we analyzed differential expression of genes between the dorsal and ventral hippocampus of rats in polyA-enriched samples and samples subjected to depletion of ribosomal RNA. We present here a detailed analysis of differentially expressed genes between the dorsal and ventral parts of the hippocampus. Intersection of our dataset with data of previous RNAseq studies revealed 544 genes are stably differentially expressed between the hippocampal parts suggesting that, despite strongly variability between the animals and sequencing approaches, there is a subset of genes whose expression stably differs between the dorsal and ventral hippocampus. Analysis of differential splicing showed that the dorsal and ventral parts of the hippocampus express 64 genes whose splice isoforms are different between the hippocampal parts. Furthermore, we show that depletion of ribosomal RNA increases representation of transposable elements in the RNAseq libraries and helps to detect a weak predominance of expression of these elements in the ventral hippocampus. Overall design: 7 male rats were analyzed using polyA-enrichment RNAseq and 3 male rats were analyzed using RNAseq after depletion of ribosomal RNA. Dorsal and ventral parts of the hippocampus were dissected in every animal.