Single-cell discovery of mA RNA modifications in the hippocampus.

-Methyladenosine (mA) is a prevalent and highly regulated RNA modification essential for RNA metabolism and normal brain function. It is particularly important in the hippocampus, where mA is implicated in neurogenesis and learning. Although extensively studied, its presence in specific cell types remains poorly understood. We investigated mA in the hippocampus at a single-cell resolution, revealing a comprehensive landscape of mA modifications within individual cells. Through our analysis, we uncovered transcripts exhibiting a dense mA profile, notably linked to neurological disorders such as Alzheimer's disease. Our findings suggest a pivotal role of mA-containing transcripts, particularly in the context of CAMK2A neurons. Overall, this work provides new insights into the molecular mechanisms underlying hippocampal physiology and lays the foundation for future studies investigating the dynamic nature of mA RNA methylation in the healthy and diseased brain.