PNRC2 (proline-rich nuclear receptor coactivator 2) functions primarily as a molecular adaptor linking mRNA surveillance and decapping machinery. It acts as a bridge between the mRNA decaying complex and UPF1, a key component of nonsense-mediated mRNA decay (NMD) 1. Structurally, PNRC2's proline-rich region binds the EVH1 domain of decapping enzyme Dcp1a, while its NR-box interacts with hyperphosphorylated UPF1, enabling PNRC2 to recruit decapping machinery to aberrant mRNAs and facilitate their degradation 2. PNRC2 also localizes to P-bodies and is required for UPF1 P-body localization 1. Beyond NMD, PNRC2 participates in ligand-dependent glucocorticoid receptor-mediated mRNA degradation by recruiting UPF1 and DCP1A to target transcripts 3. It regulates cyclic gene transcripts during vertebrate somitogenesis through cooperation with Pumilio proteins and AU-rich element-binding proteins 4. Additionally, PNRC2 serves as a nuclear receptor coactivator 5. Clinically, PNRC2 dysregulation associates with malignant meningioma progression 6 and hepatocellular carcinoma, particularly in Mongolian populations with hepatitis D viral infection 7. PNRC2 also functions in adipogenesis where it facilitates Staufen1-mediated mRNA decay of antiadipogenic factors 8.