Post-transcriptional gene regulation is robustly regulated by RNA-binding proteins (RBPs). Here we describe the collection of RNAs regulated by AUF1 (AU-binding factor 1), an RBP linked to cancer, inflammation and aging. Photoactivatable ribonucleoside-enhanced crosslinking and immunoprecipitation (PAR-CLIP) analysis reveals that AUF1 primarily recognizes U-/GU-rich sequences in mRNAs and noncoding RNAs and influences target transcript fate in three main directions. First, AUF1 lowers the steady-state levels of numerous target RNAs, including long noncoding RNA NEAT1, in turn affecting the organization of nuclear paraspeckles. Second, AUF1 does not change the abundance of many target RNAs, but ribosome profiling reveals that AUF1 promotes the translation of numerous mRNAs in this group. Third, AUF1 unexpectedly enhances the steady-state levels of several target mRNAs encoding DNA-maintenance proteins. Through its actions on target RNAs, AUF1 preserves genomic integrity, in agreement with the AUF1-elicited prevention of premature cellular senescence.