Fig 1: Identification and in vivo validation of subtype‐specific genes in primary and secondary senescence. (A) Venn diagram illustrating overlapping and unique DEGs between primary (QUI vs. IR) and secondary (QCMT vs. SCMT) senescence (adjusted p‐values < 0.05, log2FC > 0.25). Upregulated genes specific to each condition are listed. (B) Pseudotemporal expression profiles of representative primary senescence–specific DEGs enriched in the terminal primary cluster (C8). The x‐axis represents the pseudotime and the y‐axis represents the log‐normalized gene expression levels. (C) Pseudotime expression profiles of representative secondary senescence–specific DEGs enriched in the terminal secondary cluster (C3). Gene expression dynamics are shown along lineage 4 toward the terminal senescent state. (D, E) Spatial transcriptomic validation using a public mouse kidney Visium dataset (GSE252772). (D) Spatial expression of Ltbp2, a primary senescence–specific DEG and (E) Cxcl1/Cxcl2 (murine homologs of human CXCL8; secondary senescence–specific DEG) by comparing young (W3) and aged (W92) kidneys. Spatial feature maps were generated from SCTransform‐normalized Visium data merged into a single Seurat object and batch‐corrected with Harmony using sample_id. F, female; M, male; W, week; U1 indicates an individual Visium dataset identifier. The color scale represents normalized gene expression level.