MPP6/YNR024W Summary Help

Standard Name MPP6 1
Systematic Name YNR024W
Feature Type ORF, Verified
Description Nuclear exosome-associated RNA binding protein; involved in surveillance of pre-rRNAs and pre-mRNAs, and the degradation of cryptic non-coding RNAs (ncRNA); copurifies with ribosomes; relocalizes to the cytosol in response to hypoxia (1, 2, 3 and see Summary Paragraph)
Name Description M-Phase Phosphoprotein 6 homologue 1
Chromosomal Location
ChrXIV:672409 to 672969 | ORF Map | GBrowse
Gbrowse
Gene Ontology Annotations All MPP6 GO evidence and references
  View Computational GO annotations for MPP6
Molecular Function
Manually curated
Biological Process
Manually curated
Cellular Component
Manually curated
High-throughput
Regulators 3 genes
Resources
Classical genetics
null
Large-scale survey
null
Resources
68 total interaction(s) for 37 unique genes/features.
Physical Interactions
  • Affinity Capture-MS: 39
  • Affinity Capture-Western: 3
  • Co-fractionation: 1
  • Co-purification: 1

Genetic Interactions
  • Dosage Rescue: 1
  • Negative Genetic: 10
  • Phenotypic Enhancement: 2
  • Phenotypic Suppression: 1
  • Positive Genetic: 4
  • Synthetic Growth Defect: 3
  • Synthetic Lethality: 3

Resources
Expression Summary
histogram
Resources
Length (a.a.) 186
Molecular Weight (Da) 21,142
Isoelectric Point (pI) 10.09
Localization
Phosphorylation PhosphoGRID | PhosphoPep Database
Structure
Homologs
sequence information
ChrXIV:672409 to 672969 | ORF Map | GBrowse
SGD ORF map
Last Update Coordinates: 2011-02-03 | Sequence: 1997-01-28
Subfeature details
Relative
Coordinates
Chromosomal
Coordinates
Most Recent Updates
Coordinates Sequence
CDS 1..561 672409..672969 2011-02-03 1997-01-28
Retrieve sequences
Analyze Sequence
S288C only
S288C vs. other species
S288C vs. other strains
Resources
External Links All Associated Seq | Entrez Gene | Entrez RefSeq Protein | MIPS | Search all NCBI (Entrez) | UniProtKB
Primary SGDIDS000005307
SUMMARY PARAGRAPH for MPP6

The exosome complex possesses 3'-5' exonuclease and endoribonucleolytic activities that are essential for diverse ribonucleolytic processes in both the nucleus and the cytoplasm (4, 5, 6). The nuclear exosome is associated with the TRAMP complex and is involved in RNA catabolic processes including RNA surveillance (7, 8 and references therein), pre-mRNA turnover (9) and the production of mature 3' ends for snoRNAs, snRNAs and rRNAs (5, 10 and references therein). The cytoplasmic exosome is associated with Ski7p and the SKI complex and is involved in RNA catabolic processes that include both the routine turnover of normal mRNA (11) as well as the degradation of aberrant mRNAs (12 and references therein). The 10-subunit core exosome complex (Csl4p, Rrp4p, Rrp40p, Ski6p, Rrp42p, Rrp43p, Rrp45p, Rrp46p, Mtr3p, Dis3p) is the same in both locations, but the nuclear exosome contains an additional subunit (Rrp6p) and two additional accessory factors (Lrp1p, Mpp6p) (6).

Although the exosome was originally described as a "complex of exonucleases," with multiple subunits proposed to have RNase activity (4), later work has shown that this mechanism is unlikely in yeast. With the exception of Ski6p, none of the yeast subunits that show homology to E. coli RNase PH retain the active site residues seen in the bacterial or archael enzymes. Further research has also demonstrated that most, if not all, detectable enzymatic activity resides in the Dis3p and Rrp6p subunits (13, 14).

Last updated: 2009-09-09 Contact SGD

References cited on this page View Complete Literature Guide for MPP6
1) Milligan L, et al.  (2008) A yeast exosome cofactor, Mpp6, functions in RNA surveillance and in the degradation of noncoding RNA transcripts. Mol Cell Biol 28(17):5446-57
2) Fleischer TC, et al.  (2006) Systematic identification and functional screens of uncharacterized proteins associated with eukaryotic ribosomal complexes. Genes Dev 20(10):1294-307
3) Ghosh Dastidar R, et al.  (2012) The nuclear localization of SWI/SNF proteins is subjected to oxygen regulation. Cell Biosci 2(1):30
4) Mitchell P, et al.  (1997) The exosome: a conserved eukaryotic RNA processing complex containing multiple 3'-->5' exoribonucleases. Cell 91(4):457-66
5) van Hoof A, et al.  (2000) Yeast exosome mutants accumulate 3'-extended polyadenylated forms of U4 small nuclear RNA and small nucleolar RNAs. Mol Cell Biol 20(2):441-52
6) Synowsky SA, et al.  (2009) Comparative multiplexed mass spectrometric analyses of endogenously expressed yeast nuclear and cytoplasmic exosomes. J Mol Biol 385(4):1300-13
7) Vanacova S, et al.  (2005) A new yeast poly(A) polymerase complex involved in RNA quality control. PLoS Biol 3(6):e189
8) LaCava J, et al.  (2005) RNA degradation by the exosome is promoted by a nuclear polyadenylation complex. Cell 121(5):713-24
9) Bousquet-Antonelli C, et al.  (2000) Identification of a regulated pathway for nuclear pre-mRNA turnover. Cell 102(6):765-75
10) Allmang C, et al.  (2000) Degradation of ribosomal RNA precursors by the exosome. Nucleic Acids Res 28(8):1684-91
11) Jacobs JS, et al.  (1998) The 3' to 5' degradation of yeast mRNAs is a general mechanism for mRNA turnover that requires the SKI2 DEVH box protein and 3' to 5' exonucleases of the exosome complex. EMBO J 17(5):1497-506
12) Schaeffer D, et al.  (2008) Determining in vivo activity of the yeast cytoplasmic exosome. Methods Enzymol 448:227-39
13) Liu Q, et al.  (2006) Reconstitution, activities, and structure of the eukaryotic RNA exosome. Cell 127(6):1223-37
14) Dziembowski A, et al.  (2007) A single subunit, Dis3, is essentially responsible for yeast exosome core activity. Nat Struct Mol Biol 14(1):15-22