Polyadenylate-binding protein 1 is a protein that in humans is encoded by the PABPC1 gene.[5] The protein PABP1 binds mRNA and facilitates a variety of functions such as transport into and out of the nucleus, degradation, translation, and stability. There are two separate PABP1 proteins, one which is located in the nucleus (PABPN1) and the other which is found in the cytoplasm (PABPC1). The location of PABP1 affects the role of that protein and its function with RNA.[6]

PABPC1
Available structures
PDBOrtholog search: PDBe RCSB
Identifiers
AliasesPABPC1, PAB1, PABP, PABP1, PABPC2, PABPL1, poly(A) binding protein cytoplasmic 1
External IDsOMIM: 604679 MGI: 1349722 HomoloGene: 37638 GeneCards: PABPC1
Orthologs
SpeciesHumanMouse
Entrez
Ensembl
UniProt
RefSeq (mRNA)

NM_002568

NM_008774

RefSeq (protein)

NP_002559

NP_032800

Location (UCSC)Chr 8: 100.69 – 100.72 MbChr 15: 36.6 – 36.61 Mb
PubMed search[3][4]
Wikidata
View/Edit HumanView/Edit Mouse

Function edit

The poly(A)-binding protein (PAB or PABP), which is found complexed to the 3' poly(A) tail of eukaryotic mRNA, is required for poly(A) lengthening and the termination of translation. In humans, the PABPs comprise a small nuclear isoform and a conserved gene family of other poly(A)-binding proteins.[supplied by OMIM][7]

PABPC1 is usually diffused within the cytoplasm and concentrated at sites of high mRNA concentration such as stress granules, processing bodies, and locations of high translational activity. PABPC1 is also associated with nonsense-mediated mRNA decay (NMD). PABPC1 binds to the poly(A) tail and interact with eIF4G, which stabilizes the circularization of mRNAs. This structure is required for the prevention of mRNA degradation via NMD.[8]

In the nucleus PABP1 binds to the poly(A) tails of pre-mRNAs to facilitate stability, export, transport, and degradation. PABP1 binding is also required for nuclear-mediated degradation. PABPC1 contains four RNA-recognition motifs (RRMs). The first two, RRM1 and RRM2, bind both α-importin and the poly(A) tail of processed mRNA. This feature prevents mRNA from going back into the nucleus.[6]

Interactions edit

PABPC1 has been shown to interact with:

References edit

  1. ^ a b c GRCh38: Ensembl release 89: ENSG00000070756 - Ensembl, May 2017
  2. ^ a b c GRCm38: Ensembl release 89: ENSMUSG00000022283 - Ensembl, May 2017
  3. ^ "Human PubMed Reference:". National Center for Biotechnology Information, U.S. National Library of Medicine.
  4. ^ "Mouse PubMed Reference:". National Center for Biotechnology Information, U.S. National Library of Medicine.
  5. ^ Grange T, de Sa CM, Oddos J, Pictet R (June 1987). "Human mRNA polyadenylate binding protein: evolutionary conservation of a nucleic acid binding motif". Nucleic Acids Research. 15 (12): 4771–87. doi:10.1093/nar/15.12.4771. PMC 305917. PMID 2885805.
  6. ^ a b Gray NK, Hrabálková L, Scanlon JP, Smith RW (December 2015). "Poly(A)-binding proteins and mRNA localization: who rules the roost?". Biochemical Society Transactions. 43 (6): 1277–84. doi:10.1042/BST20150171. PMID 26614673.
  7. ^ "Entrez Gene: PABPC1 poly(A) binding protein, cytoplasmic 1".
  8. ^ Fatscher T, Boehm V, Weiche B, Gehring NH (October 2014). "The interaction of cytoplasmic poly(A)-binding protein with eukaryotic initiation factor 4G suppresses nonsense-mediated mRNA decay". RNA. 20 (10): 1579–92. doi:10.1261/rna.044933.114. PMC 4174440. PMID 25147240.
  9. ^ Koloteva-Levine N, Pinchasi D, Pereman I, Zur A, Brandeis M, Elroy-Stein O (May 2004). "The Apc5 subunit of the anaphase-promoting complex/cyclosome interacts with poly(A) binding protein and represses internal ribosome entry site-mediated translation". Molecular and Cellular Biology. 24 (9): 3577–87. doi:10.1128/mcb.24.9.3577-3587.2004. PMC 387753. PMID 15082755.
  10. ^ Funakoshi Y, Doi Y, Hosoda N, Uchida N, Osawa M, Shimada I, Tsujimoto M, Suzuki T, Katada T, Hoshino S (December 2007). "Mechanism of mRNA deadenylation: evidence for a molecular interplay between translation termination factor eRF3 and mRNA deadenylases". Genes & Development. 21 (23): 3135–48. doi:10.1101/gad.1597707. PMC 2081979. PMID 18056425.
  11. ^ a b Imataka H, Gradi A, Sonenberg N (December 1998). "A newly identified N-terminal amino acid sequence of human eIF4G binds poly(A)-binding protein and functions in poly(A)-dependent translation". The EMBO Journal. 17 (24): 7480–9. doi:10.1093/emboj/17.24.7480. PMC 1171091. PMID 9857202.
  12. ^ Hoshino S, Imai M, Kobayashi T, Uchida N, Katada T (June 1999). "The eukaryotic polypeptide chain releasing factor (eRF3/GSPT) carrying the translation termination signal to the 3'-Poly(A) tail of mRNA. Direct association of erf3/GSPT with polyadenylate-binding protein". The Journal of Biological Chemistry. 274 (24): 16677–80. doi:10.1074/jbc.274.24.16677. PMID 10358005.
  13. ^ Roy G, De Crescenzo G, Khaleghpour K, Kahvejian A, O'Connor-McCourt M, Sonenberg N (June 2002). "Paip1 interacts with poly(A) binding protein through two independent binding motifs". Molecular and Cellular Biology. 22 (11): 3769–82. doi:10.1128/mcb.22.11.3769-3782.2002. PMC 133836. PMID 11997512.
  14. ^ Craig AW, Haghighat A, Yu AT, Sonenberg N (April 1998). "Interaction of polyadenylate-binding protein with the eIF4G homologue PAIP enhances translation". Nature. 392 (6675): 520–3. Bibcode:1998Natur.392..520C. doi:10.1038/33198. PMID 9548260. S2CID 10891925.
  15. ^ Khaleghpour K, Kahvejian A, De Crescenzo G, Roy G, Svitkin YV, Imataka H, O'Connor-McCourt M, Sonenberg N (August 2001). "Dual interactions of the translational repressor Paip2 with poly(A) binding protein". Molecular and Cellular Biology. 21 (15): 5200–13. doi:10.1128/MCB.21.15.5200-5213.2001. PMC 87244. PMID 11438674.

Further reading edit