Project description:Arginyltransferase ATE1 mediates posttranslational arginylation that plays key roles in mammalian embryogenesis, cell migration, and normal brain function. The molecular mechanisms of arginylation remain elusive. ATE1 utilizes arginyl-tRNAArg as the donor of Arg, putting this reaction into a direct competition with the protein synthesis machinery. Here, we addressed these questions of ATE1- arginyl-tRNAArg specificity as a potential mechanism enabling this competition in vivo. Using in vitro arginylation assays and ATE1 knockout models, we find that while arginylation is specific to tRNAArg, it is able to utilize short tRNAArg derivatives that bear structural resemblance to tRNA-derived fragments (tRF), a new class of small regulatory non-coding RNAs with poorly characterized but critical functions in vivo. Arginyl-tRFArg can be generated in vitro directly from pre-charged -tRNAArg, and ATE1 is able to utilize these arginyl-tRFArg fragments with similar efficiency as arginyl-tRNAArg. Lack of arginylation in ATE1 knockout cells leads to a decrease in tRFArg generation and a significant increase in the ratio of tRNAArg to tRFArg compared to wild type, suggesting a functional link between tRFArg and arginylation in vivo. We propose that generation of physiologically important tRFs can play a critical role as a switch between protein translation and arginylation in vivo.
Project description:Arginyltransferase ATE1 mediates posttranslational arginylation that plays key roles in mammalian embryogenesis, cell migration, and normal brain function. The molecular mechanisms of arginylation remain elusive. ATE1 utilizes arginyl-tRNAArg as the donor of Arg, putting this reaction into a direct competition with the protein synthesis machinery. Here, we addressed these questions of ATE1- arginyl-tRNAArg specificity as a potential mechanism enabling this competition in vivo. Using in vitro arginylation assays and ATE1 knockout models, we find that while arginylation is specific to tRNAArg, it is able to utilize short tRNAArg derivatives that bear structural resemblance to tRNA-derived fragments (tRF), a new class of small regulatory non-coding RNAs with poorly characterized but critical functions in vivo. Arginyl-tRFArg can be generated in vitro directly from pre-charged -tRNAArg, and ATE1 is able to utilize these arginyl-tRFArg fragments with similar efficiency as arginyl-tRNAArg. Lack of arginylation in ATE1 knockout cells leads to a decrease in tRFArg generation and a significant increase in the ratio of tRNAArg to tRFArg compared to wild type, suggesting a functional link between tRFArg and arginylation in vivo. We propose that generation of physiologically important tRFs can play a critical role as a switch between protein translation and arginylation in vivo.
Project description:In order to intensively elucidate the metabolic characteristics of tRFs after liver injury, we performed tRF-seq by high throughput sequencing. We found that after liver injury, large abundance of tRFs were produced. Especially, the tRF-1s largely vary during the liver injury process and may play important role in the liver disease.
Project description:Transfer-RNA-Derived Small RNA (tsRNA) is a novel class of short non-coding RNA including stress-induced tRNA fragments (tiRNA) and tRNA-derived fragments (tRF). Using RNA sequencing, we evaluated the tsRNA expression profiles in the serum of sarcoidosis (n = 3) compared with healthy control group (n = 3). Bioinformatics analyses indicated that tsRNAs were the important regulators and potential new biomarkers of sarcoidosis.
Project description:tRNA related fragments(tRF) and tRNA halves(tiRNA) are novel class of short non-coding RNA derived from tRNAs. Using RNA sequencing, we evaluated the tRFs/tiRNAs expression profiles in relapsed/refractory multiple myeloma and multiple myeloma patients. Bioinformatics analyses indicated that tRFs/tiRNAs may be involved in the progression and drug-resistance of multiple myeloma.
Project description:tRNA-derived small RNAs (tsRNA) are a new type of noncoding RNAs that can be mainly classified into two groups: tRFs (tRNA-derived fragments) and tiRNAs (tRNA halves). The abnormal expression of tsRNAs is known to play an important role in the biological progression of breast cancer. However, it's still unclear about the mechanism of tsRNAs in cancer. tRF-1-Ser is a tRF that is high expression in breast cancer and negatively regulated by 25(OH)D. Our study aims to find out the effect of tRF-1-Ser on breast cancer and explore the change of RNA in tRF-1-Ser knock-down breast cancer cells.
Project description:Transfer RNA-derived fragments (tRFs) and transfer RNA halves (tiRNAs) have been shown to play crucial roles in gene regulation. This study targets to reveal the expression profile of tRFs and tiRNAs and their possible biological roles in lung adenocarcinoma (LUAD). Five paired clinical lung adenocarcinoma tissues (LAT) and adjacent normal lung tissues (ANLT) were selected to conduct the expression of tRFs and tiRNAs. The sequencing results showed that 109 tRFs and tiRNAs were differentially expressed between LAT and ANLT, out of which 60 were upregulated and 49 were downregulated. Compared with ANLT, lower expression levels of three tRF-1s (tRF-Ser-TGA-010, tRF-Arg-CCT-018 and tRF-Val-CAC-017) in LAT were verified by quantitative real-time polymerase chain reaction. Subsequently, the putative target genes of tRF-1s were analyzed by computational prediction and the top ten significant results of GO and KEGG pathway enrichment analysis were presented. These signaling pathways are involved in the carcinogenesis of LUAD. This study has showed a landscape of tRFs and tiRNAs expression profiles in LUAD. Three newly found differentially expressed down-regulated tRF-1s may be involved in the pathogenesis of LUAD and might serve as potential diagnostic biomarkers.