Yeast Helicase Pif1 Unwinds RNA:DNA Hybrids with Higher Processivity than DNA:DNA Duplexes
| Autor: | Alicia K. Byrd, Shubeena Chib, Kevin D. Raney |
|---|---|
| Rok vydání: | 2016 |
| Předmět: |
0301 basic medicine
Saccharomyces cerevisiae Proteins DNA polymerase Base pair DNA polymerase II Saccharomyces cerevisiae Biochemistry 03 medical and health sciences DNA Fungal Molecular Biology Adenosine Triphosphatases DNA clamp biology Circular bacterial chromosome DNA Helicases Nucleic Acid Hybridization RNA Fungal Cell Biology Processivity Kinetics 030104 developmental biology Enzymology biology.protein DNA supercoil Primase |
| Zdroj: | Journal of Biological Chemistry. 291:5889-5901 |
| ISSN: | 0021-9258 |
| DOI: | 10.1074/jbc.m115.688648 |
| Popis: | Saccharomyces cerevisiae Pif1, an SF1B helicase, has been implicated in both mitochondrial and nuclear functions. Here we have characterized the preference of Pif1 for RNA:DNA heteroduplexes in vitro by investigating several kinetic parameters associated with unwinding. We show that the preferential unwinding of RNA:DNA hybrids is due to neither specific binding nor differences in the rate of strand separation. Instead, Pif1 is capable of unwinding RNA:DNA heteroduplexes with moderately greater processivity compared with its duplex DNA:DNA counterparts. This higher processivity of Pif1 is attributed to slower dissociation from RNA:DNA hybrids. Biologically, this preferential role of the helicase may contribute to its functions at both telomeric and nontelomeric sites. |
| Databáze: | OpenAIRE |
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