Disease relevance of RNP1

• The influenza virus NS2 protein, which had no previously assigned function, was shown to mediate the nuclear export of virion RNAs by acting as an adaptor between viral ribonucleoprotein complexes and the nuclear export machinery of the cell [1].
• Autoantibodies against U3 small nuclear ribonucleoprotein are associated with scleroderma autoimmune disease [2].
• The bipartite 3'-cis-acting signal for replication is required for formation of a ribonucleoprotein complex in vivo between the viral genome and its RNA polymerase in yeast 23 S RNA virus [3].
• The multifunctional herpes simplex virus IE63 protein interacts with heterogeneous ribonucleoprotein K and with casein kinase 2 [4].
• The phylogenetically distant rabies virus (PV strain, genotype 1) and Mokola virus (genotype 3) were used to develop a strategy to identify functional homologous interactive domains from two proteins (P and N) which participate in the viral ribonucleoprotein (RNP) transcription-replication complex [5].

High impact information on RNP1

• Selective transport of mRNAs in ribonucleoprotein particles (mRNP) ensures asymmetric distribution of information within and among eukaryotic cells [6].
• The division of labor between RNA and protein illustrated by this simple system reveals principles applicable to complex ribonucleoprotein assemblies such as the spliceosome and ribosome [7].
• We find that ribonucleoprotein particles from yeast mitochondria contain a reverse transcriptase activity that is likely encoded by al1 and al2 and is highly specific for the introns and their flanking exons [8].
• It is proposed that this represents an ATP-dependent interaction between small nuclear ribonucleoprotein particles that precedes their entry into the spliceosome [9].
• A large nucleolar U3 ribonucleoprotein required for 18S ribosomal RNA biogenesis [10].

Biological context of RNP1

• The RNP1 gene maps to the left arm of chromosome XIV centromere distal to SUF10 [11].
• Two null mutants of RNP1 that were created, a frameshift disruption and a complete deletion of the gene, were viable, demonstrating that the gene is not essential for cell growth [12].
• Internal sequence information of purified p60 reveals identity with the open reading frames of genes PUB1 and RNP1 which encode polyuridylate binding protein(s) [13].
• However genomic Southern blot analysis indicated that several other loci in the S. cerevisiae genome appear to contain sequences similar to those in the RNP1 gene [11].
• Haploid yeast containing a null allele of RNP1 are viable, indicating that RNP1 is dispensible for mitotic growth [11].

Anatomical context of RNP1

• A fraction of Rnp1 protein cosediments on sucrose gradients with 40S and 60S ribosomal subunits and 80S monosomes, but not with polyribosomes [11].
• On micro-injection into the cytoplasm of Xenopus oocytes, the snRNAs are packaged into ribonucleoprotein particles and migrate into the nucleus [14].
• The signal recognition particle (SRP) is an evolutionarily conserved ribonucleoprotein (RNP) complex that functions in protein targeting to the endoplasmic reticulum (ER) membrane [15].
• We propose a model where Mlp1p acts as a checkpoint at the nuclear pore by interacting with export-competent ribonucleoprotein complexes through its C-terminal globular domain [16].
• In neural cells, such as oligodendrocytes and neurons, transport of certain RNAs along microtubules is mediated by the cis-acting heterogeneous nuclear ribonucleoprotein A2 response element (A2RE) trafficking element and the cognate trans-acting heterogeneous nuclear ribonucleoprotein (hnRNP) A2 trafficking factor [17].

Associations of RNP1 with chemical compounds

• Thus, arginine methylation serves to mask the Npl3p RGG domain for efficient ribonucleoprotein export [18].
• Nrd1 has hallmarks of a heterogeneous nuclear ribonucleoprotein, including an RNA recognition motif, a region rich in RE and RS dipeptides, and a proline- and glutamine-rich domain [19].
• In wild-type strains, p62 remains associated with the excised intron lariat RNA in ribonucleoprotein (RNP) particles that are essential for intron homing [20].
• Studies of RNA-protein interactions in the yeast 5 S ribonucleoprotein particles by fluorescence and tritium exchange. Implications for ribosomal assembly [21].
• In archaea and eukaryotes, these conversions are performed by box H/ACA small ribonucleoprotein particles (box H/ACA RNPs), which contain a small guide RNA responsible for the selection of substrate uridines and four proteins, including the pseudouridine synthase, Cbf5p [22].

Physical interactions of RNP1

• In this work we show that TcUBP-1 is part of an approximately 450-kDa ribonucleoprotein complex with a poly(A)-binding protein and a novel 18-kDa RNA-binding protein, named TcUBP-2 [23].
• Bud-specific enrichment depends on Myo4p's association with its cargo, a ribonucleoprotein complex containing the RNA-binding protein She2p [24].
• Scp160p is an RNA-binding protein containing 14 tandemly repeated heterogenous nuclear ribonucleoprotein K-homology domains, which are implicated in RNA binding [25].
• This ribonucleoprotein complex is transported to the distal tip of the bud along polarized actin cables [26].
• A novel ribonucleoprotein complex enriched in nucleolar proteins was purified from yeast extracts and constituents were identified by mass spectrometry [27].

Other interactions of RNP1

• NOP4 encodes a 78 kDa protein that contains two prototypical RNA recognition motifs (RRMs) flanking an imperfect RRM lacking characteristic RNP1 and RNP2 motifs [28].
• The NAB3 gene is essential for cell viability and encodes an acidic ribonucleoprotein [29].
• In Saccharomyces cerevisiae, the single poly(A) binding protein, Pab1, is the major ribonucleoprotein associated with the poly(A) tails of mRNAs in both the nucleus and the cytoplasm [30].
• Interaction of the RNP1 motif in PRT1 with HCR1 promotes 40S binding of eukaryotic initiation factor 3 in yeast [31].
• One of these, Npl3p, is a heterogeneous nuclear ribonucleoprotein-like protein with some similarity to SR proteins and is essential for growth in the yeast S. cerevisiae [32].

Analytical, diagnostic and therapeutic context of RNP1

• This interaction was also detected in vivo by co-immunoprecipitation of the ribonucleoprotein complex and using yeast two-hybrid assay [23].
• To study the biochemistry of ribonucleoprotein export from the nucleus, we characterized an in vivo assay in which the cytoplasmic appearance of radiolabeled ribosomal subunits was monitored after their microinjection into Xenopus oocyte nuclei [33].
• Based on sedimentation, immunoprecipitation and Western blot analyses we conclude that this RNA is part of a stable ribonucleoprotein (RNP) complex and associated not only with the p277 protein, but also with the common proteins present in the other trans-spliceosomal snRNPs [34].
• Molecular cloning of cDNA for the nuclear ribonucleoprotein particle C proteins: a conserved gene family [35].
• Immunoprecipitations with the antibodies indicated that the PRP4 protein is associated with the U4/U6 small nuclear ribonucleoprotein particle [36].

References