Long non-coding RNA LINC02499 regulates the expression of CYP3A5 in human liver cells

Cytochrome P450 3A5 (CYP3A5) is a critical drug-metabolizing enzyme in human hepatocytes, playing a key role in the metabolism of various clinically relevant drugs, with considerable variability in gene expression across individuals. Long non-coding RNAs (lncRNAs) are likely to be important regulators within the CYP3A5 regulatory network in the liver. In this study, we employed a computational approach to estimate Sobol's sensitivity indices (SSI) under generalized linear models, applied to liver RNA expression microarray data (GTEx v8). The SSI-based analysis revealed that the long non-coding RNA LINC02499 exhibits the highest SSI value in relation to CYP3A5 expression in the liver. Furthermore, we conducted a comprehensive evaluation of LINC02499's biological characteristics and confirmed its regulatory role in CYP3A5 expression through real-time quantitative PCR and Western blotting experiments at the cellular level. We also demonstrated the direct interaction between miR-329-5p and both LINC02499 and CYP3A5 mRNA using dual-luciferase reporter assays and electrophoretic mobility shift assays (EMSA). In conclusion, our findings outline a regulatory network in which LINC02499 functions as a molecular sponge, mitigating the post-transcriptional inhibitory effect of miR-329-5p on CYP3A5 expression.