Ribosomal RNA processing protein 1 homolog A (RRP1)

Ribosomal RNA processing protein 1 homolog A (RRP1, also called Nop52 or NNP-1) is an **essential, evolutionarily conserved nucleolar protein** involved in the processing of precursor ribosomal RNA (pre-rRNA) during the biogenesis of the large (60S) ribosomal subunit[1][2]. RRP1/Nop52 mediates late stages of nucleologenesis at the end of mitosis and is required for the maturation of 28S rRNA in humans[2]. It acts as a key mediator in the conversion of large pre-ribosomal particles into functional subunits by facilitating and integrating specific cleavage events in the pre-rRNA, working with factors such as p32, fibrillarin, and exonuclease XRN2[2]. Loss or mutation of RRP1 leads to defects in ribosome biogenesis that ultimately affect protein synthesis and cell growth[1][2]. RRP1 has also emerged as a clinical interest molecule, with distinct transcripts differentially expressed in some cancers and suggested as potential biomarkers for diagnosis and prognosis, for example in neuroblastoma[2]. There are currently no drugs known to specifically target RRP1, and it is not considered a classical therapeutic drug target such as an enzyme, receptor, or ion channel[2].

Other names

Ribosomal RNA processing 1D21S2056ENNP1NNP-1Nop52NOP52RRP1ANovel nuclear protein 1Nucleolar protein Nop52RRP1-like proteinNnp1 homologDNA segment on chromosome 21 (unique) 2056 expressed sequenceNucleolar protein (Drosophila)Protein NNP-1