Dysregulation of tRNA-derived small RNAs and their potential roles in lupus nephritis.

OBJECTIVE: Lupus nephritis (LN) is a major end-organ complication of systemic lupus erythematosus (SLE), and the molecular mechanism of LN is not completely clear. Accumulating pieces of evidence indicate the potential vital role of tRNA-derived small RNAs (tsRNAs) in human diseases. Current study aimed to investigate the potential roles of tsRNAs in LN.

METHODS: We herein employed high-throughput sequencing to screen the expression profiles of tsRNAs in renal tissues of the LN and control groups. To validate the sequencing data, we performed quantitative real-time PCR (qRT-PCR) analysis. Correlational analysis of verified tsRNAs expression and clinical indicators was conducted using linear regression. The potential target genes were also predicted. The biological functions of tsRNAs were annotated by Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis.

RESULTS: Our findings revealed that the expression profiles of tsRNAs were significantly altered in the kidney tissues from LN patients compared with control. Overall, 160 tsRNAs were significantly dysregulated in the LN group, of which 79 were upregulated, whereas 81 were downregulated. Subsequent qRT-PCR results confirmed the different expression of candidate tsRNAs. Correlation analysis results found that expression of verified tsRNAs were correlated to clinical indicators. The target prediction results revealed that verified tsRNAs might act on 712 target genes. Further bioinformatics analysis uncovered tsRNAs might participate in the pathogenesis of LN through several associated pathways, including cell adhesion molecules, MAPK signaling pathway, PI3K-Akt signaling pathway and B cell receptor signaling pathway.

CONCLUSION: This study provides a novel insight for studying the mechanism of LN.