Insulin-like growth factor 2 receptor

Insulin-like growth factor 2 receptor

PDB rendering based on 1e6f.
Identifiers
Symbols IGF2R; CD222; CIMPR; M6P-R; MPR1; MPRI
External IDs OMIM147280 MGI96435 HomoloGene676 GeneCards: IGF2R Gene
RNA expression pattern
More reference expression data
Orthologs
Species Human Mouse
Entrez 3482 16004
Ensembl ENSG00000197081 ENSMUSG00000023830
UniProt P11717 Q7TMR1
RefSeq (mRNA) NM_000876.2 NM_010515.2
RefSeq (protein) NP_000867.2 NP_034645.2
Location (UCSC) Chr 6:
160.39 – 160.53 Mb
Chr 17:
12.88 – 12.96 Mb
PubMed search [1] [2]

In the fields of biochemistry and cell biology, the insulin-like growth factor 2 receptor (IGF2R), also called the cation-independent mannose-6-phosphate receptor (CI-MPR) is a protein that in humans is encoded by the IGF2R gene.[1][2] IGF2R is a multifunctional protein receptor that binds insulin-like growth factor 2 (IGF2) at the cell surface and mannose-6-phosphate (M6P)-tagged proteins in the trans-Golgi network.[2]

Contents

Structure

The structure of the IGF2R is a type I transmembrane protein (that is, it has a single transmembrane domain with its C-terminus on the cytoplasmic side of lipid membranes) with a large extracellular/lumenal domain and a relatively short cytoplasmic tail.[3] The extracellular domain consists a small region homologous to the collagen-binding domain of fibronectin and of fifteen repeats of approximately 147 amino acid residues. Each of these repeats is homologous to the 157-residue extracytoplasmic domain of the mannose 6-phosphate receptor. Binding to IGF2 is mediated through one of the repeats, while two different repeats are responsible for binding to mannose-6-phosphate. The IGF2R is approximately 300 kDa in size it appears to exist and function as a dimer.

Function

IGF2R functions to clear IGF2 from the cell surface to attenuate signalling, and to transport lysosomal acid hydrolase precursors from the Golgi apparatus to the lysosome. After binding IGF2 at the cell surface, IGF2Rs accumulate in forming clathrin-coated vesicles and are internalized. In the lumen of the trans-Golgi network, the IGF2R binds M6P-tagged cargo.[3] The IGF2Rs (bound to their cargo) are recognized by the GGA family of clathrin adaptor proteins and accumulate in forming clathrin-coated vesicles.[4] IGF2Rs from both the cell surface and the Golgi are trafficked to the early endosome where, in the relatively low pH environment of the endosome, the IGF2Rs release their cargo. The IGF2Rs are recycled back to the Golgi by the retromer complex, again by way of interaction with GGAs and vesicles. The cargo proteins are then trafficked to the lysosome via the late endosome independently of the IGF2Rs.

Interactions

Insulin-like growth factor 2 receptor has been shown to interact with M6PRBP1.[5][6]

See also

References

  1. ^ Oshima A, Nolan CM, Kyle JW, Grubb JH, Sly WS (February 1988). "The human cation-independent mannose 6-phosphate receptor. Cloning and sequence of the full-length cDNA and expression of functional receptor in COS cells". J. Biol. Chem. 263 (5): 2553–62. PMID 2963003. 
  2. ^ a b Laureys G, Barton DE, Ullrich A, Francke U (October 1988). "Chromosomal mapping of the gene for the type II insulin-like growth factor receptor/cation-independent mannose 6-phosphate receptor in man and mouse". Genomics 3 (3): 224–9. doi:10.1016/0888-7543(88)90083-3. PMID 2852162. 
  3. ^ a b Ghosh P, Dahms NM, Kornfeld S (March 2003). "Mannose 6-phosphate receptors: new twists in the tale". Nat. Rev. Mol. Cell Biol. 4 (3): 202–12. doi:10.1038/nrm1050. PMID 12612639. 
  4. ^ Ghosh P, Kornfeld S (July 2004). "The GGA proteins: key players in protein sorting at the trans-Golgi network". Eur. J. Cell Biol. 83 (6): 257–62. doi:10.1078/0171-9335-00374. PMID 15511083. 
  5. ^ Díaz E, Pfeffer SR (May 1998). "TIP47: a cargo selection device for mannose 6-phosphate receptor trafficking". Cell 93 (3): 433–43. doi:10.1016/S0092-8674(00)81171-X. PMID 9590177. 
  6. ^ Orsel JG, Sincock PM, Krise JP, Pfeffer SR (August 2000). "Recognition of the 300-kDa mannose 6-phosphate receptor cytoplasmic domain by 47-kDa tail-interacting protein". Proc. Natl. Acad. Sci. U.S.A. 97 (16): 9047–51. doi:10.1073/pnas.160251397. PMC 16819. PMID 10908666. http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=16819. 

Further reading

External links