Super-resolution imaging informed scRNA sequencing analysis reveals the critical role of GDF15 in rejuvenating aged hematopoietic stem cells.

Although changes in mitochondrial morphology consistently associated with the aging of hematopoietic stem cells (HSCs), the specific molecular and cellular mechanisms involved are partially unclear. Live-cell super-resolution (SR) microscopy has been used to identify distinct HSC subsets that characterized by mitochondria unique morphologies and spatial distributions. The integration of SR microscopy with single-cell RNA sequencing enabled the classification of approximately 200 HSCs from young and aged mice into 5 discrete clusters. These clusters displayed molecular profiles that corresponded to the observed mitochondria states. An integrated approach combining RNA biomarker analysis and potential regulon assessment revealed previously unrecognized roles of GDF15 in mediating mitochondrial signals and morphologies that influence HSC fate. Thus, combining SR imaging with a bioinformatics pipeline provides an effective method for identifying key molecular players in specific phases of cellular transition, even with a relatively small dataset.