Pseudouridine synthase 1: a site-specific synthase without strict sequence recognition requirements
| Autor: | Jeffrey R. Patton, Bryan S. Sibert |
|---|---|
| Rok vydání: | 2011 |
| Předmět: |
Genetics
Base Sequence Base pair Nucleic Acid Enzymes Point mutation Mutant RNA Biology Pseudouridine A-site chemistry.chemical_compound chemistry Recognition sequence Biochemistry Transfer RNA otorhinolaryngologic diseases Mutagenesis Site-Directed Humans Nucleic Acid Conformation Base Pairing Hydro-Lyases RNA Transfer Ser |
| Zdroj: | Nucleic Acids Research |
| ISSN: | 1362-4962 |
| Popis: | Pseudouridine synthase 1 (Pus1p) is an unusual site-specific modification enzyme in that it can modify a number of positions in tRNAs and can recognize several other types of RNA. No consensus recognition sequence or structure has been identified for Pus1p. Human Pus1p was used to determine which structural or sequence elements of human tRNA(Ser) are necessary for pseudouridine (Ψ) formation at position 28 in the anticodon stem-loop (ASL). Some point mutations in the ASL stem of tRNA(Ser) had significant effects on the levels of modification and compensatory mutation, to reform the base pair, restored a wild-type level of Ψ formation. Deletion analysis showed that the tRNA(Ser) TΨC stem-loop was a determinant for modification in the ASL. A mini-substrate composed of the ASL and TΨC stem-loop exhibited significant Ψ formation at position 28 and a number of mutants were tested. Substantial base pairing in the ASL stem (3 out of 5 bp) is required, but the sequence of the TΨC loop is not required for modification. When all nucleotides in the ASL stem other than U28 were changed in a single mutant, but base pairing was retained, a near wild-type level of modification was observed. |
| Databáze: | OpenAIRE |
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