VEGFR-1/Flt-1 (D3), soluble

• Description:

  Recombinant human soluble Vascular Endothelial Growth Factor Receptor-1 domain D1-3 (sVEGFR-1 (D3) ) is produced as a non-chimeric protein in a monomeric form. The soluble receptor protein contains only the first 3 extracellular domains, which contain all the information necessary for binding of VEGF. The receptor monomers have a mass of approximately 45 kDa containing 352 amino acid residues. Endothelial cells express three different vascular endothelial growth factor (VEGF) receptors, belonging to the family of receptor tyrosine kinases (RTKs) . They are named VEGFR-1 (Flt-1), VEGFR-2 (KDR/Flk-1), VEGFR-3 (Flt-4) . Their expression is almost exclusively restricted to endothelial cells, but VEGFR-1 can also be found on monocytes, dendritic cells and on trophoblast cells. The flt-1 gene was first described in 1990. The receptor contains seven immunoglobulin-like extracellular domains, a single transmembrane region and an intracellular splited tyrosine kinase domain. Compared to VEGFR-2 the Flt-1 receptor has a higher affinity for VEGF but a weaker signaling activity. VEGFR-1 thus leads not to proliferation of endothelial cells, but mediates signals for differentiation. Interestingly a naturally occuring soluble variant of VEGFR-1 (sVEGFR-1) was found in HUVEC supernatants in 1996, which is generated by alternative splicing of the flt-1 mRNA. The biological functions of sVEGFR-1 still are not clear, but it seems to be an endogenous regulator of angiogenesis, binding VEGF with the same affinity as the full-length receptor.

• Synonyms:

  Soluble vascular endothelial growth factor receptor-1; soluble FLT1; soluble VEGFR-1

• NCBI Gene ID:

  2321

• UniProt:

  P17948

• Accession Number:

  NP_001153392

• Accession Number mRNA:

  NM_001159920

• Chromosomal Location:

  13q12

• Reactivity:

  Human

• Cross Reactivity:

  Human

• Sequence:

  SKLKDPELSLKGTQHIMQAGQTLHLQCRGEAAHKWSLPEMVSKESERLSITKSACGRNGKQFCSTLTLNTAQANHTGFYSCKYLAVPTSKKKETESAIYIFISDTGRPFVEMYSEIPEIIHMTEGRELVIPCRVTSPNITVTLKKFPLDTLIPDGKRIIWDSRKGFIISNATYKEIGLLTCEATVNGHLYKTNYLTHRQTNTIIDVQISTPRPVKLLRGHTLVLNCTATTPLNTRVQMTWSYPDEKNKRASVRRRIDQSNSHANIFYSVLTIDKMQNKDKGLYTCRVRSGPSFKSVNTSVHIYDKAFITVKHRKQQVLETVAGKRSY

• Assay Protocol:

  The lyophilized sVEGFR-1 (D3) is soluble in water and most aqueous buffers and should be reconstituted in PBS to a concentration not lower than 100µg/ml.

• Purity:

  > 90% by SDS-PAGE

• Bioactivity:

  The activity of sVEGFR-1 (D3) was determined by its ability to inhibit the VEGF-A-induced proliferation of HUVECs.

• Length:

  327

• Form:

  Lyophilized

• Buffer:

  PBS

• Reconstitution:

  Water

• Molecular Weight:

  45.0 kDa

• Storage Conditions:

  Lyophilized samples are stable for greater than six months at -20°C to -70°C. Reconstituted sVEGFR-1 (D3) should be stored in working aliquots at -70°C.

• Host or Source:

  Insect cells

• N Terminal Sequence:

  SKLKD