- 作者: Sue Lin-Chao; Ni-Ting Chiou; Gadi Schuster
- 作者服務機構: 1 Institute of Molecular Biology, Academia S璯ica, Taipei, 11529, Taiwan; ; 2 Department of Biology, Technion - Israel Institute of Technology, Haifa, 32000, Israel
- 中文摘要: --
- 英文摘要: The structure and function of polynucleotide phosphorylase (PNPase) and the exosome, as well as their associated RNA-helicases proteins, are described in the light of recent studies. The picture raised is of an evolutionarily conserved RNA-degradation machine which exonucleolytically degrades RNA from 3' to 5'. In prokaryotes and in eukaryotic organelles, a trimeric complex of PNPase forms a circular doughnut-shaped structure, in which the phosphorolysis catalytic sites are buried inside the barrel-shaped complex, while the RNA binding domains create a pore where RNA enters, reminiscent of the protein degrading complex, the proteasome. In some archaea and in the eukaryotes, several different proteins form a similar circle-shaped complex, the exosome, that is responsible for 3' to 5' exonucleolytic degradation of RNA as part of the processing, quality control, and general RNA degradation process. Both PNPase in prokaryotes and the exosome in eukaryotes are found in association with protein complexes that notably include RNA helicase.
- 中文關鍵字: --
- 英文關鍵字: RNase PH, PNPase, Exosome, RNA helicase, RNA degradation, RNA polyadenylation