Generation of piRNAs (IMAGE) European Molecular Biology Laboratory Caption In germline cells PIWI proteins silence the RNA from jumping genes by cutting them in sequences of ~30 nucleotides that will become piRNAs. These new piRNAs bind to a nuclear PIWI protein to repress the expression of the jumping gene in the nucleus. Credit Ramesh Pillai/EMBL Usage Restrictions None License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.