RPP2B/YDR382W Summary Help

Standard Name RPP2B 1
Systematic Name YDR382W
Alias RPL45 , YPA1
Feature Type ORF, Verified
Description Ribosomal protein P2 beta; a component of the ribosomal stalk, which is involved in the interaction between translational elongation factors and the ribosome; free (non-ribosomal) P2 stimulates the phosphorylation of the eIF2 alpha subunit (Sui2p) by Gcn2p; regulates the accumulation of P1 (Rpp1Ap and Rpp1Bp) in the cytoplasm (2, 3, 4 and see Summary Paragraph)
Name Description Ribosomal Protein P2 Beta 2
Gene Product Alias L45 2 , P2B 2 , YP2beta 2
Chromosomal Location
ChrIV:1239492 to 1239824 | ORF Map | GBrowse
Gene Ontology Annotations All RPP2B GO evidence and references
  View Computational GO annotations for RPP2B
Molecular Function
Manually curated
Biological Process
Manually curated
Cellular Component
Manually curated
Regulators 8 genes
Classical genetics
Large-scale survey
282 total interaction(s) for 203 unique genes/features.
Physical Interactions
  • Affinity Capture-MS: 91
  • Affinity Capture-RNA: 10
  • Affinity Capture-Western: 11
  • Biochemical Activity: 3
  • Co-fractionation: 1
  • Co-purification: 1
  • PCA: 3
  • Reconstituted Complex: 6
  • Two-hybrid: 6

Genetic Interactions
  • Dosage Lethality: 1
  • Dosage Rescue: 1
  • Negative Genetic: 120
  • Phenotypic Suppression: 2
  • Positive Genetic: 13
  • Synthetic Growth Defect: 12
  • Synthetic Rescue: 1

Expression Summary
Length (a.a.) 110
Molecular Weight (Da) 11,050
Isoelectric Point (pI) 3.89
Phosphorylation PhosphoGRID | PhosphoPep Database
sequence information
ChrIV:1239492 to 1239824 | ORF Map | GBrowse
Last Update Coordinates: 2011-02-03 | Sequence: 1996-07-31
Subfeature details
Most Recent Updates
Coordinates Sequence
CDS 1..333 1239492..1239824 2011-02-03 1996-07-31
Retrieve sequences
Analyze Sequence
S288C only
S288C vs. other species
S288C vs. other strains
External Links All Associated Seq | Entrez Gene | Entrez RefSeq Protein | MIPS | Search all NCBI (Entrez) | UniProtKB
Primary SGDIDS000002790

About yeast ribosomes...

Ribosomes are highly conserved large ribonucleoprotein (RNP) particles, consisting in yeast of a large 60S subunit and a small 40S subunit, that perform protein synthesis. Yeast ribosomes contain one copy each of four ribosomal RNAs (5S, 5.8S, 18S, and 25S; produced in two separate transcripts encoded within the rDNA repeat present as hundreds of copies on Chromosome 12) and 79 different ribosomal proteins (r-proteins), which are encoded by 137 different genes scattered about the genome, 59 of which are duplicated (5, 6). The 60S subunit contains 46 proteins and three RNA molecules: 25S RNA of 3392 nt, hydrogen bonded to the 5.8S RNA of 158 nt and associated with the 5S RNA of 121 nt. The 40S subunit has a single 18S RNA of 1798 nt and 33 proteins (7, 6). All yeast ribosomal proteins have a mammalian homolog (1).

In a rapidly growing yeast cell, 60% of total transcription is devoted to ribosomal RNA, and 50% of RNA polymerase II transcription and 90% of mRNA splicing are devoted to the production of mRNAs for r-proteins. Coordinate regulation of the rRNA genes and 137 r-protein genes is affected by nutritional cues and a number of signal transduction pathways that can abruptly induce or silence the ribosomal genes, whose transcripts have naturally short lifetimes, leading to major implications for the expression of other genes as well (8, 9, 10). The expression of some r-protein genes is influenced by Abf1p (11), and most are directly induced by binding of Rap1p to their promoters, which excludes nucleosomes and recruits Fhl1p and Ifh1p to drive transcription (12).

Ribosome assembly is a complex process, with different steps occurring in different parts of the cell. Ribosomal protein genes are transcribed in the nucleus, and the mRNA is transported to the cytoplasm for translation. The newly synthesized r-proteins then enter the nucleus and associate in the nucleolus with the two rRNA transcripts, one of which is methylated and pseudouridylated (view sites of modifications), and then cleaved into three individual rRNAs (18S, 5.8S, and 25S) as part of the assembly process (5). Separate ribosomal subunits are then transported from the nucleolus to the cytoplasm where they assemble into mature ribosomes before functioning in translation (13, 14). Blockage of subunit assembly, such as due to inhibition of rRNA synthesis or processing, results in degradation of newly synthesized r-proteins (15, 14). (For more information on the early steps of rRNA processing and small ribosomal subunit assembly, see the summary paragraph for the U3 snoRNA, encoded by snR17A and snR17B.)

About ribosomal stalk proteins ...

The ribosome has a lateral protuberance called the stalk that interacts with elongation factor EF2 (Eft1p, Eft2p) (16). The stalk is formed by five acidic proteins organized as a pentameric complex (P0-[P1A-P2B]/[P1B-P2A]), with P0 acting as an anchor linking the stalk to the ribosome and directly interacting with the large rRNA GTPase-associated domain (17, 18). P0 is encoded by RPP0, P1 by RPP1A and RPP1B, and P2 by RPP2A and RPP2B. The P2 proteins are on the periphery of the stalk complex, shielding the P1 proteins, which interact with P0 (19). P0 is a scaffolding protein with two short amino acid regions located at positions 199-230 and 231-258 that are responsible for independent binding of two heterodimers, P1A-P2B and P1B-P2A, respectively (17, 18). The P1A-P2B heterodimer is the key element in stalk formation, and the P1B-P2A heterodimer has been implicated in regulation of stalk function (17). The yeast P0, P1, and P2 proteins are homologous to the mammalian P0, P1, and P2 proteins (1).

Last updated: 2007-02-22 Contact SGD

References cited on this page View Complete Literature Guide for RPP2B
1) Mager WH, et al.  (1997) A new nomenclature for the cytoplasmic ribosomal proteins of Saccharomyces cerevisiae. Nucleic Acids Res 25(24):4872-5
2) Planta RJ and Mager WH  (1998) The list of cytoplasmic ribosomal proteins of Saccharomyces cerevisiae. Yeast 14(5):471-7
3) Nusspaumer G, et al.  (2000) Phosphorylation and N-terminal region of yeast ribosomal protein P1 mediate its degradation, which is prevented by protein P2. EMBO J 19(22):6075-84
4) Jimenez-Diaz A, et al.  (2013) Phosphorylation of Initiation Factor eIF2 in Response to Stress Conditions Is Mediated by Acidic Ribosomal P1/P2 Proteins in Saccharomyces cerevisiae. PLoS One 8(12):e84219
5) Venema J and Tollervey D  (1999) Ribosome synthesis in Saccharomyces cerevisiae. Annu Rev Genet 33:261-311
6) Jenner L, et al.  (2012) Crystal structure of the 80S yeast ribosome. Curr Opin Struct Biol 22(6):759-67
7) Verschoor A, et al.  (1998) Three-dimensional structure of the yeast ribosome. Nucleic Acids Res 26(2):655-61
8) Li B, et al.  (1999) Transcriptional elements involved in the repression of ribosomal protein synthesis. Mol Cell Biol 19(8):5393-404
9) Zhao Y, et al.  (2003) Autoregulation in the biosynthesis of ribosomes. Mol Cell Biol 23(2):699-707
10) Warner JR  (1999) The economics of ribosome biosynthesis in yeast. Trends Biochem Sci 24(11):437-40
11) Mager WH and Planta RJ  (1990) Multifunctional DNA-binding proteins mediate concerted transcription activation of yeast ribosomal protein genes. Biochim Biophys Acta 1050(1-3):351-5
12) Zhao Y, et al.  (2006) Fine-structure analysis of ribosomal protein gene transcription. Mol Cell Biol 26(13):4853-62
13) Moritz M, et al.  (1990) Depletion of yeast ribosomal proteins L16 or rp59 disrupts ribosome assembly. J Cell Biol 111(6 Pt 1):2261-74
14) Milgrom E, et al.  (2007) Loss of vacuolar proton-translocating ATPase activity in yeast results in chronic oxidative stress. J Biol Chem 282(10):7125-36
15) Wang S, et al.  (2007) Influence of Substrate Conformation on the Deglycosylation of Ribonuclease B by Recombinant Yeast Peptide:N-glycanase. Acta Biochim Biophys Sin (Shanghai) 39(1):8-14
16) Santos C and Ballesta JP  (2005) Characterization of the 26S rRNA-binding domain in Saccharomyces cerevisiae ribosomal stalk phosphoprotein P0. Mol Microbiol 58(1):217-26
17) Krokowski D, et al.  (2005) Acquisition of a stable structure by yeast ribosomal P0 protein requires binding of P1A-P2B complex: in vitro formation of the stalk structure. Biochim Biophys Acta 1724(1-2):59-70
18) Krokowski D, et al.  (2006) Yeast ribosomal P0 protein has two separate binding sites for P1/P2 proteins. Mol Microbiol 60(2):386-400
19) Hanson CL, et al.  (2004) Mass spectrometry of ribosomes from Saccharomyces cerevisiae: implications for assembly of the stalk complex. J Biol Chem 279(41):42750-7