Insulin-like growth factor-binding protein

(Redirected from Insulin-like growth factor binding protein) Transport protein for insulin-like growth factor 1

Insulin-like growth factor
binding protein

Structure of the IGF-binding domain of the insulin-like growth factor-binding protein-5 (IGFBP-5)

Identifiers

Symbol

IGFBP

1boe / SCOPe / SUPFAM

Available protein structures:
Pfam	structures / ECOD
PDB	RCSB PDB; PDBe; PDBj
PDBsum	structure summary
PDB	1boe, 1h59

The insulin-like growth factor-binding protein (IGFBP) serves as a transport protein for insulin-like growth factor 1 (IGF-1).

Function

Approximately 98% of IGF-1 is always bound to one of six binding proteins (IGF-BP). IGFBP-3, the most abundant protein, accounts for 80% of all IGF binding. IGF-1 binds to IGFBP-3 in a 1:1 molar ratio. IGF-BP also binds to IGF-1 inside the liver, allowing growth hormone to continuously act upon the liver to produce more IGF-1.

IGF binding proteins (IGFBPs) are proteins of 24 to 45 kDa. All six IGFBPs share 50% homology with each other and have binding affinities for IGF-I and IGF-II at the same order of magnitude as the ligands have for the IGF-IR.

The IGFBPs help to lengthen the half-life of circulating IGFs in all tissues, including the prostate. Individual IGFBPs may act to enhance or attenuate IGF signaling depending on their physiological context (i.e. cell type). Even with these similarities, some characteristics are different: chromosomal location, heparin binding domains, RGD recognition site, preference for binding IGF-I or IGF-II, and glycosylation and phosphorylation differences. These structural differences can have a tremendous impact on how the IGFBPs interact with cellular basement membranes.

Family members

In humans, IGFBPs are transcribed from the following seven genes:

References

Kalus W, Zweckstetter M, Renner C, et al. (November 1998). "Structure of the IGF-binding domain of the insulin-like growth factor-binding protein-5 (IGFBP-5): implications for IGF and IGF-I receptor interactions" (PDF). EMBO J. 17 (22): 6558–72. doi:10.1093/emboj/17.22.6558. PMC 1171003. PMID 9822601.
Hwa V, Oh Y, Rosenfeld RG (December 1999). "The insulin-like growth factor-binding protein (IGFBP) superfamily". Endocr. Rev. 20 (6): 761–87. doi:10.1210/edrv.20.6.0382. PMID 10605625.
Clemmons DR, Busby WH, Arai T, Nam TJ, Clarke JB, Jones JI, Ankrapp DK (1995). "Role of insulin-like growth factor binding proteins in the control of IGF actions". Prog. Growth Factor Res. 6 (2–4): 357–66. doi:10.1016/0955-2235(95)00013-5. PMID 8817679.
Stewart CE, Bates PC, Calder TA, Woodall SM, Pell JM (September 1993). "Potentiation of insulin-like growth factor-I (IGF-I) activity by an antibody: supportive evidence for enhancement of IGF-I bioavailability in vivo by IGF binding proteins". Endocrinology. 133 (3): 1462–5. doi:10.1210/endo.133.3.7689959. PMID 7689959.
Gregory CW, DeGeorges A, Sikes RA (2001). "The IGF axis in the development and progression of prostate cancer". Recent Research Developments in Cancer: 437–462. ISBN 81-7895-002-2.

External links

Insulin-like+growth+factor+binding+proteins at the U.S. National Library of Medicine Medical Subject Headings (MeSH)

v t e Proteins: carrier proteins
Fatty acid	FABP1 FABP2 FABP3 FABP4 FABP5 FABP6 FABP7
Hormone	peptide hormone: Follistatin Growth hormone binding protein Insulin-like growth factor binding protein IGFBP1 IGFBP2 IGFBP3 IGFBP4 IGFBP5 IGFBP6 IGFBP7 Neurophysins Neurophysin I II steroid hormone: Sex hormone binding globulin/Androgen binding protein Transcortin Thyroxine-binding globulin Transthyretin
Metal/element	calcium Calcium-binding protein Calmodulin-binding proteins copper Ceruloplasmin iron Iron-binding proteins Transferrin receptor
Vitamin	Retinol binding protein 1 2 3 4 Transcobalamin
Pigment	Plant Light-Harvesting Complex Orange Carotenoid Protein Phycobiliprotein Photosynthetic Reaction Centers Phytochrome Rhodopsin
Other	Acyl carrier protein Adaptor protein Cholesterylester transfer protein F-box protein GTP-binding protein Latent TGF-beta binding protein Major urinary proteins Membrane transport protein Odorant binding protein

Growth factor receptor modulators

Angiopoietin

Agonists: Angiopoietin 1
Angiopoietin 4

Antagonists: Angiopoietin 2
Angiopoietin 3

Kinase inhibitors: Altiratinib
CE-245677
Rebastinib

Antibodies: Evinacumab (against angiopoietin 3)
Nesvacumab (against angiopoietin 2)

CNTF

Agonists: Axokine
CNTF
Dapiclermin

EGF (ErbB)

EGF (ErbB1/HER1)	Agonists: Amphiregulin Betacellulin EGF (urogastrone) Epigen Epiregulin Heparin-binding EGF-like growth factor (HB-EGF) Murodermin Nepidermin Transforming growth factor alpha (TGFα) Kinase inhibitors: Afatinib Agerafenib Brigatinib Canertinib Dacomitinib Erlotinib Gefitinib Grandinin Icotinib Lapatinib Neratinib Osimertinib Vandetanib WHI-P 154 Antibodies: Cetuximab Depatuxizumab Depatuxizumab mafodotin Futuximab Imgatuzumab Matuzumab Necitumumab Nimotuzumab Panitumumab Zalutumumab
ErbB2/HER2	Agonists: Unknown/none Antibodies: Ertumaxomab Pertuzumab Trastuzumab Trastuzumab deruxtecan Trastuzumab duocarmazine Trastuzumab emtansine Kinase inhibitors: Afatinib Lapatinib Mubritinib Neratinib Tucatinib
ErbB3/HER3	Agonists: Neuregulins (heregulins) (1, 2, 6 (neuroglycan C)) Antibodies: Duligotumab Patritumab Seribantumab
ErbB4/HER4	Agonists: Betacellulin Epigen Heparin-binding EGF-like growth factor (HB-EGF) Neuregulins (heregulins) (1, 2, 3, 4, 5 (tomoregulin, TMEFF))

FGF

FGFR1	Agonists: Ersofermin FGF (1, 2 (bFGF), 3, 4, 5, 6, 8, 10 (KGF2), 20) Repifermin Selpercatinib Trafermin Velafermin
FGFR2	Agonists: Ersofermin FGF (1, 2 (bFGF), 3, 4, 5, 6, 7 (KGF), 8, 9, 10 (KGF2), 17, 18, 22) Palifermin Repifermin Selpercatinib Sprifermin Trafermin Antibodies: Aprutumab Aprutumab ixadotin Kinase inhibitors: Infigratinib
FGFR3	Agonists: Ersofermin FGF (1, 2 (bFGF), 4, 8, 9, 18, 23) Selpercatinib Sprifermin Trafermin Antibodies: Burosumab (against FGF23)
FGFR4	Agonists: Ersofermin FGF (1, 2 (bFGF), 4, 6, 8, 9, 19) Trafermin
Unsorted	Agonists: FGF15/19

HGF (c-Met)

Agonists: Fosgonimeton
Hepatocyte growth factor

Potentiators: Dihexa (PNB-0408)

IGF

IGF-1

IGF-2

Agonists: Insulin-like growth factor-2 (somatomedin A)

Antibodies: Dusigitumab
Xentuzumab (against IGF-1 and IGF-2)

Others

Binding proteins: IGFBP (1, 2, 3, 4, 5, 6, 7)

Cleavage products/derivatives with unknown target: Glypromate (GPE, (1-3)IGF-1)
Trofinetide

LNGF (p75)

Antibodies: Against NGF: ABT-110 (PG110)
ASP-6294
Fasinumab
Frunevetmab
Fulranumab
MEDI-578
Ranevetmab
Tanezumab

Aptamers: Against NGF: RBM-004

Decoy receptors: LEVI-04 (p75-Fc)

PDGF

Agonists: Becaplermin
Platelet-derived growth factor (A, B, C, D)

RET (GFL)

GFRα1	Agonists: Glial cell line-derived neurotrophic factor (GDNF) Liatermin Kinase inhibitors: Vandetanib
GFRα2	Agonists: Neurturin (NRTN) Kinase inhibitors: Vandetanib
GFRα3	Agonists: Artemin (ARTN) Kinase inhibitors: Vandetanib
GFRα4	Agonists: Persephin (PSPN) Kinase inhibitors: Vandetanib
Unsorted	Kinase inhibitors: Agerafenib