Nucleolar protein 9 (NOP9)

Nucleolar protein 9 (NOP9) is a conserved RNA-binding protein belonging to the Pumilio repeat protein family (PUF), characterized by eleven PUM repeats arranged in a C-shaped fold[1][2]. It is an essential factor for the processing and maturation of preribosomal RNA, required for assembly and nuclear maturation of small ribosomal (pre-40S) subunits, most notably through its role in correct processing of 20S pre-rRNA to mature 18S rRNA[1][2][3]. NOP9 recognizes both single-stranded and structured RNA elements in pre-rRNA, and functions by preventing premature cleavage of 20S pre-rRNA by the nuclease Nob1, thus ensuring proper maturation and timing of ribosome assembly[1][2]. Loss or defects of NOP9 in model organisms are lethal, and in humans, perturbation of its function has been associated with breast cancer, certain neurodevelopmental disorders, and autoimmune pathologies[2]. NOP9 is not established as a direct therapeutic target or receptor, and no interacting drugs or clinical biomarkers have been identified.

Other names

NOP9C14orf21KIAA2021HP08474nucleolar protein 9 homologhypothetical protein HP08474pumilio domain-containing protein C14orf21