Transcriptomic analysis of Perirhinal and Lateral Entorhinal cortex regions in mice.

The perirhinal cortex (PER) is crucial for object recognition memory and comprises areas 35 and 36 (A35 and A36). The lateral entorhinal cortex (LEC), subdivided into dorsolateral (DLE), dorsal intermediate (DIE), and ventral intermediate (VIE) regions, plays a key role in encoding representations of objects, events, contextual details, and sequential information. Despite their anatomical distinctions, gene expression profiling of these subregions remains limited. To address this gap, we conducted transcriptome analysis of these regions in C57BL/6 mice. Tissue samples were collected using laser microdissection, isolating A35, A36, DLE, and VIE, and subsequently they were analyzed via RNA sequencing. Our results revealed no significant gene expression differences between PER A35 and A36, yet substantial molecular divergence emerged when comparing PER to LEC subregions. The PER exhibited higher expression of genes related to nutritional state sensitivity compared to the LEC, while the DLE showed elevated expression of genes implicated in axonal guidance, neurotrophic support, and glutamatergic neurotransmission relative to the VIE. These findings advance our understanding of the molecular profiles unique to PER and LEC regions, and may support the generation of novel hypotheses regarding functional roles of these cortical populations that may be explored in future research.