Cloned (Comment) | Organism |
---|---|
gene PARN, recombinant expression of His-tagged wild-type and mutant enzymes in Escherichia coli strain Rosetta | Homo sapiens |
Protein Variants | Comment | Organism |
---|---|---|
H377A | site-directed mutagenesis, catalytic inactive mutant | Homo sapiens |
additional information | enzyme knockout by siRNA in HeLa cells | Homo sapiens |
Localization | Comment | Organism | GeneOntology No. | Textmining |
---|---|---|---|---|
additional information | PARN co-purifies with 40S subunit precursors | Homo sapiens | - |
- |
nucleolus | nucleolar steady-state localization | Homo sapiens | 5730 | - |
nucleus | PARN occurs in the nucleus, upstream of the final endonucleolytic cleavage by the endonuclease NOB1 in the cytoplasm | Homo sapiens | 5634 | - |
Metals/Ions | Comment | Organism | Structure |
---|---|---|---|
Mg2+ | required | Homo sapiens |
Organism | UniProt | Comment | Textmining |
---|---|---|---|
Homo sapiens | O95453 | - |
- |
Purification (Comment) | Organism |
---|---|
recombinant His-tagged wild-type and mutant enzymes from Escherichia coli strain Rosetta by nickel affinity tandem chromatography and anion exchange chromatography | Homo sapiens |
Substrates | Comment Substrates | Organism | Products | Comment (Products) | Rev. | Reac. |
---|---|---|---|---|---|---|
18S-E pre-rRNA + H2O | different 18S-E pre-rRNAs | Homo sapiens | ? | - |
? | |
additional information | enzyme PARN performs exonucleolytic trimming of 18S-E pre-rRNA, and PARN can process the corresponding ITS1 RNA fragment in vitro | Homo sapiens | ? | - |
? |
Synonyms | Comment | Organism |
---|---|---|
PARN | - |
Homo sapiens |
Temperature Optimum [°C] | Temperature Optimum Maximum [°C] | Comment | Organism |
---|---|---|---|
30 | - |
assay at | Homo sapiens |
pH Optimum Minimum | pH Optimum Maximum | Comment | Organism |
---|---|---|---|
7.5 | - |
assay at | Homo sapiens |
General Information | Comment | Organism |
---|---|---|
malfunction | knocking down ribosome biogenesis factors (RBFs) involved in the large subunit pathway (LSG1 and eIF6) has no effect on PARN localization. Co-depletion of PARN and NOB1 yields a much stronger accumulation of 18S-EFL species than the sole knockdown of PARN. This suggests that NOB1 can also cleave untrimmed 18S-E pre-rRNAs, albeit less efficiently. In accordance with this assumption, overexpression of NOB1 in PARN-depleted cells leads to a decreased amount of 18S-EFL pre-rRNA | Homo sapiens |
metabolism | the enzyme plays a role in mRNA catabolism and in exonucleolytic trimming of 18S-E pre-rRNA | Homo sapiens |
physiological function | poly(A)-specific ribonuclease is a nuclear ribosome biogenesis factor involved in human 18S rRNA maturation. The enzyme supports the processing of different types of non-coding RNAs including telomerase RNA. PARN is part of the enzymatic machinery that matures the human 18S ribosomal RNA (rRNA). PARN is required for 40S ribosomal subunit production. Function of PARN in exonucleolytic trimming of 18S-E pre-rRNA. A number of nucleolar 40S-specific ribosome biogenesis factors (RBFs), including ENP1, DIM2, RRP12, LTV1 and TSR1, accompany pre-40S particles from the nucleolus via the nucleoplasm to the cytosol. Like shuttling nucleolar RBFs, PARN redistributes from the nucleolus to the nucleoplasm upon inhibition of pre-40S particle export by leptomycin B. PARN is coupled to a poly(A) polymerase for processing of the 18S-E pre-rRNA. PARN is primarily involved in pre-rRNA processing, not in quality control | Homo sapiens |