Miriam Olombrada, Cohue Peña, Olga Rodríguez-Galán, Purnima Klingauf-Nerurkar, Daniela Portugal-Calisto, Michaela Oborská-Oplová, Martin Altvater, José G Gavilanes, Álvaro Martínez-Del-Pozo, Jesús de la Cruz, Lucía García-Ortega, Vikram Govind Panse
The ribotoxin α-sarcin belongs to a family of ribonucleases that cleave the sarcin/ricin loop (SRL), a critical functional rRNA element within the large ribosomal subunit (60S), thereby abolishing translation. Whether α-sarcin targets the SRL only in mature 60S subunits remains unresolved. Here, we show that, in yeast, α-sarcin can cleave SRLs within late 60S pre-ribosomes containing mature 25S rRNA but not nucleolar/nuclear 60S pre-ribosomes containing 27S pre-rRNA in vivo. Conditional expression of α-sarcin is lethal, but does not impede early pre-rRNA processing, nuclear export and the cytoplasmic maturation of 60S pre-ribosomes...
May 4, 2020: Nucleic Acids Research