Cloned (Comment) | Organism |
---|---|
expression of N-terminally His-tagged wild-type and mutant enzymes in Escherichia coli strain BL21-CodonPlus (DE3)-RIPL | Homo sapiens |
Crystallization (Comment) | Organism |
---|---|
wild-type and S1 domain-truncated hPNPase, hanging-drop vapor diffusion method, mixxing of 0.001 ml of 10 mg/ml protein in 50 mM Tris, pH 8.0, and 150 mM NaCl, with 0.001 ml of reservoir solution containing 0.1 M citrate, pH 5.0, 10% v/v 2-propanol and 26% v/v PEG 400, room temperature, X-ray diffraction structure determination and analysis at 2.1 A resolution, molecular replacement method | Homo sapiens |
Protein Variants | Comment | Organism |
---|---|---|
G622D | site-directed mutagenesis | Homo sapiens |
additional information | generation of a S1 domain-lacking mutant enzyme, domain organization of full-length and S1 domain-truncated hPNPase. overview. Full-length and DELTAS1 hPNPase cleave the poly(A)12 and poly(U)12 RNA with similar activities and DELTAS1 hPNPase cleaves ssRNA substrate almost as efficiently as full-length PNPase | Homo sapiens |
Localization | Comment | Organism | GeneOntology No. | Textmining |
---|---|---|---|---|
exosome | structure of the S1 pore in exosomes and the KH pore in hPNPase, overview | Homo sapiens | - |
- |
additional information | KH pore in PNPase versus S1 pore in exosomes | Homo sapiens | - |
- |
Metals/Ions | Comment | Organism | Structure |
---|---|---|---|
Mg2+ | required | Homo sapiens |
Molecular Weight [Da] | Molecular Weight Maximum [Da] | Comment | Organism |
---|---|---|---|
80900 | - |
3 * 80900, about, sequence calculation, the trimeric hPNPase has a hexameric ring-like structure formed by six RNase PH domains, capped with a trimeric KH pore, the enzyme has a conserved GXXG motif in the KH domain, structural model of hPNPase, overview | Homo sapiens |
240000 | - |
recombinant enzyme, gel filtration | Homo sapiens |
Natural Substrates | Organism | Comment (Nat. Sub.) | Natural Products | Comment (Nat. Pro.) | Rev. | Reac. |
---|---|---|---|---|---|---|
RNAn+1 + phosphate | Homo sapiens | the enzyme catalyzes the processive phosphorolysis of RNA by using an inorganic phosphate to cleave the phosphodiester linkage at the 3'-end of a RNA chain | RNAn + a nucleoside diphosphate | - |
? |
Organism | UniProt | Comment | Textmining |
---|---|---|---|
Homo sapiens | G8TCS8 | - |
- |
Purification (Comment) | Organism |
---|---|
recombinant N-terminally His-tagged wild-type and mutant enzymes from Escherichia coli strain BL21-CodonPlus (DE3)-RIPL by nickel affinty chromatography and gel filtration | Homo sapiens |
Substrates | Comment Substrates | Organism | Products | Comment (Products) | Rev. | Reac. |
---|---|---|---|---|---|---|
additional information | full-length and DELTAS1 hPNPase cleave the poly(A)12 and poly(U)12 RNA with similar activities and DELTAS1 hPNPase cleaves ssRNA substrate almost as efficiently as full-length PNPase | Homo sapiens | ? | - |
? | |
RNAn+1 + phosphate | the enzyme catalyzes the processive phosphorolysis of RNA by using an inorganic phosphate to cleave the phosphodiester linkage at the 3'-end of a RNA chain | Homo sapiens | RNAn + a nucleoside diphosphate | - |
? | |
RNAn+1 + phosphate | the functional trimeric phosphorylase is capable of digesting single-stranded RNA to produce final products of about 4 nt in length | Homo sapiens | RNAn + a nucleoside diphosphate | - |
? |
Subunits | Comment | Organism |
---|---|---|
More | domain organization of full-length and S1 domain-truncated hPNPase. overview | Homo sapiens |
trimer | 3 * 80900, about, sequence calculation, the trimeric hPNPase has a hexameric ring-like structure formed by six RNase PH domains, capped with a trimeric KH pore, the enzyme has a conserved GXXG motif in the KH domain, structural model of hPNPase, overview | Homo sapiens |
Synonyms | Comment | Organism |
---|---|---|
PNPase | - |
Homo sapiens |
polynucleotide phosphorylase | - |
Homo sapiens |
Temperature Optimum [°C] | Temperature Optimum Maximum [°C] | Comment | Organism |
---|---|---|---|
37 | - |
assay at | Homo sapiens |
pH Optimum Minimum | pH Optimum Maximum | Comment | Organism |
---|---|---|---|
8 | - |
assay at | Homo sapiens |
General Information | Comment | Organism |
---|---|---|
additional information | the C-terminal S1 domain is not critical for RNA binding, and conversely, the conserved GXXG motif in the KH domain directly participates in RNA binding in hPNPase. The enzyme uses a KH pore to trap a long RNA 3' tail that is further delivered into an RNase PH channel for the degradation process. The three KH domains form a KH pore situated on the top of the hexameric ring-like structure. The KH pore extends the central channel formed by the RNase PH domains and is involved in the binding of RNA substrates, which are further delivered to the active site located within the central channel. Structural RNA with short 3' tails are, on the other hand, transported but not digested by hPNPase. Structural model of hPNPase, overview | Homo sapiens |
physiological function | human polynucleotide phosphorylase is a 3'-to-5' exoribonuclease that degrades specific mRNA and miRNA, and imports RNA into mitochondria, and thus regulates diverse physiological processes, including cellular senescence and homeostasis | Homo sapiens |