Project description:How mitochondrial DNA (mtDNA) polymorphisms influence complex phenotypes remains poorly understood. Using Mitochondrial-Nuclear eXchange (MNX) mice, we previously showed that mtDNA single nucleotide polymorphisms (SNP) modify metastasis, cardiovascular disease, and epigenetic marks independently of metabolic differences, suggesting a role for non-protein-coding loci. The only SNP correlating with these phenotypes resides in the gene encoding mitochondrial tRNA-Arginine (mt-tRNAArg (UCG), mt-TR). Here we identify and preliminarily characterize previously undescribed tRNA-derived fragments (tRF) generated from mt-TR. Northern blotting revealed distinct tRF that are differentially expressed between lung and liver and between sexes. Small RNA sequencing failed to capture these tRF unless samples were pre-treated to enzymatically remove non-canonical RNA termini and base methylation. Focusing on fragments with complete homology to mt-TR, the two most abundant tRF align uniquely to the mitochondrial genome and share conserved cleavage sites. Together, these findings uncover mitochondrial-derived tRF as a previously unrecognized small RNA metastasis modifiers and expand the functional output of the mitochondrial genome, supporting a model in which mtDNA-encoded tRF contribute to phenotype modification.
Project description:How mitochondrial DNA (mtDNA) polymorphisms influence complex phenotypes remains poorly understood. Using Mitochondrial-Nuclear eXchange (MNX) mice, we previously showed that mtDNA single nucleotide polymorphisms (SNP) modify metastasis, cardiovascular disease, and epigenetic marks independently of metabolic differences, suggesting a role for non-protein-coding loci. The only SNP correlating with these phenotypes resides in the gene encoding mitochondrial tRNA-Arginine (mt-tRNAArg (UCG), mt-TR). Here we identify and preliminarily characterize previously undescribed tRNA-derived fragments (tRF) generated from mt-TR. Northern blotting revealed distinct tRF that are differentially expressed between lung and liver and between sexes. Small RNA sequencing failed to capture these tRF unless samples were pre-treated to enzymatically remove non-canonical RNA termini and base methylation. Focusing on fragments with complete homology to mt-TR, the two most abundant tRF align uniquely to the mitochondrial genome and share conserved cleavage sites. Together, these findings uncover mitochondrial-derived tRF as a previously unrecognized small RNA metastasis modifiers and expand the functional output of the mitochondrial genome, supporting a model in which mtDNA-encoded tRF contribute to phenotype modification.
2026-08-07 | GSE324681 | GEO
Project description:Revision of Litoria rothii (Anura: Pelodryadidae) from northern Australia