Knockout of the Ribonuclease Inhibitor Gene Leaves Human Cells Vulnerable to Secretory Ribonucleases.
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ABSTRACT:
SUBMITTER: Thomas SP
PROVIDER: S-EPMC5148631 | biostudies-literature | 2016 Nov
REPOSITORIES: biostudies-literature
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Knockout of the Ribonuclease Inhibitor Gene Leaves Human Cells Vulnerable to Secretory Ribonucleases.
Thomas Sydney P SP Kim Eunji E Kim Jin-Soo JS Raines Ronald T RT
Biochemistry 20161108 46
Ribonuclease inhibitor (RNH1) is a cytosolic protein that binds with femtomolar affinity to human ribonuclease 1 (RNase 1) and homologous secretory ribonucleases. RNH1 contains 32 cysteine residues and has been implicated as an antioxidant. Here, we use CRISPR-Cas9 to knock out RNH1 in HeLa cells. We find that cellular RNH1 affords marked protection from the lethal ribonucleolytic activity of RNase 1 but not from oxidants. We conclude that RNH1 protects cytosolic RNA from invading ribonucleases. ...[more]
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