PubMed:9421512 JSONTXT

{"target":"https://pubannotation.org/docs/sourcedb/PubMed/sourceid/9421512","sourcedb":"PubMed","sourceid":"9421512","source_url":"http://www.ncbi.nlm.nih.gov/pubmed/9421512","text":"Effect of a mutation in the anticodon of human mitochondrial tRNAPro on its post-transcriptional modification pattern.\nAlthough the gene sequences of all 22 tRNAs encoded in the human mitochondrial genome are known, little information exists about their sequences at the RNA level. This becomes a crucial limitation when searching for a molecular understanding of the growing number of maternally inherited human diseases correlated with point mutations in tRNA genes. Here we describe the sequence of human mt-tRNAPropurified from placenta. It shows absence of editing events in this tRNA and highlights the presence of eight post-transcriptional modifications. These include T54, never found so far in an animal mt-tRNA, and m1G37, a modification known to have fundamental functional properties in a number of canonical tRNAs. Occurrence of m1G37 was further investigated in an analysis of the substrate properties of in vitro transcripts of human mt-tRNAProtowards pure Escherichia coli methylguanosine transferase. This enzyme properly methylates G37 in mt-tRNA and is sensitive to the presence of a second G at position 36, neighboring the target nucleotide for methylation. Since mutation of nt 36 was shown to be correlated with myopathy, the potential consequences of non-modification or under-modification of mt-tRNA nucleotides in expression of the particular myopathy and of mitochondrial diseases in general are discussed.","tracks":[{"project":"AnEM_abstracts","denotations":[{"id":"T1","span":{"begin":47,"end":60},"obj":"Cellular_component"},{"id":"T2","span":{"begin":184,"end":204},"obj":"Cellular_component"},{"id":"T3","span":{"begin":532,"end":540},"obj":"Organ"},{"id":"T4","span":{"begin":1386,"end":1399},"obj":"Cellular_component"}],"attributes":[{"subj":"T1","pred":"source","obj":"AnEM_abstracts"},{"subj":"T2","pred":"source","obj":"AnEM_abstracts"},{"subj":"T3","pred":"source","obj":"AnEM_abstracts"},{"subj":"T4","pred":"source","obj":"AnEM_abstracts"}]}],"config":{"attribute types":[{"pred":"source","value type":"selection","values":[{"id":"AnEM_abstracts","color":"#93ecb3","default":true}]}]}}