SSR1 (signal sequence receptor subunit 1) is a core component of the TRAP complex (SSR1-SSR4), an essential endoplasmic reticulum (ER) membrane protein complex critical for protein translocation and quality control 1. SSR1 functions as part of a calcium-binding complex that regulates ER protein retention and facilitates cotranslational and posttranslational protein targeting to the ER membrane 2. In pancreatic β-cells, SSR1 levels are essential for preproinsulin biosynthesis, with diminished expression impairing insulin protein production 2. Clinically, SSR1 is significantly upregulated across multiple cancer types. In hepatocellular carcinoma (HCC), high SSR1 expression correlates with advanced tumor stage, shorter overall survival, and serves as an independent prognostic risk factor 34. SSR1 upregulation involves promoter hypomethylation and activates cell cycle, DNA replication, and TGF-beta signaling pathways 3. SSR1 knockdown reduces HCC cell proliferation and colony formation 4. Beyond malignancy, SSR1 is upregulated in intervertebral disc degeneration and associates with monocyte infiltration 5. Additionally, SSR1 participates in glucose metabolism regulation and relates to diabetes risk 1. These findings establish SSR1 as a promising diagnostic and therapeutic biomarker in multiple disease contexts.