Arrestin-2/β-Arrestin 1

β-Arrestins, including β-arrestin 1 (ARRB1) and β-arrestin 2 (ARRB2), are multifunctional intracellular proteins that regulate G protein-coupled receptor (GPCR) desensitization, trafficking, and signal scaffolding^[1][2][3]. Mechanistically, β-arrestin 1 modulates ERK/STAT3 signaling and contributes to collagen crosslinking during renal fibrosis via the AT1R-β-arrestin pathway^[4]. In cancer models, β-arrestin 1 over-expression correlates with nuclear localization, increased VEGF expression, and poor prognosis in lung adenocarcinoma and gastric adenocarcinoma, suggesting a role in tumor progression and angiogenesis^[5][6][1]. β-Arrestin 1 also interacts with opioid receptor signaling, where its expression in peripheral blood leukocytes changes during morphine treatment and may serve as a pharmacodynamic biomarker^[7]. In metabolic and endocrine contexts, β-arrestin 1 levels influence affective symptoms in type 2 diabetes and are reduced in gestational diabetes, linking it to insulin resistance and atherogenicity^[8][9]. Compared with β-arrestin 2, β-arrestin 1 shows distinct subcellular distribution and isoform-specific interactions with nuclear signaling components, influencing transcriptional regulation and receptor-mediated endocytosis^[10][11]. Agonists or inhibitors targeting β-arrestins, such as SII or Tanshinone IIA, have been used experimentally to modulate inflammatory signaling and receptor-mediated pathways for therapeutic evaluation^[3][4]. Collectively, β-arrestin 1 exhibits isoform-specific functions in cellular signaling, disease pathophysiology, and experimental biomarker development.