VEGFR3gene structure, regulatory region, and sequence polymorphisms

Abstract

Vascular endothelial growth factor receptor 3 (VEGFR-3) is required for cardiovascular development during embryogenesis. In adults, this receptor is expressed in lymphatic endothelial cells, and mutant VEGFR3 alleles have been implicated in human hereditary lymphedema. To better understand the basis of its specific endothelial lineage-restricted expression, we have characterized the VEGFR3 gene and its regulatory 5' flanking region. The human gene contains 31 exons, of which exons 30a and 30b are alternatively spliced. The VEGFR3 proximal promoter is TATA-less and contains stretches of sequences homologous with the mouse Vegfr3 promoter region. In transfection experiments of cultured cells, the Vegfr3 promoter was shown to control endothelial cell-specific transcription of downstream reporter genes. This result was further confirmed in vivo; in a subset of transgenic mouse embryos, a 1.6 kb Vegfr3 promoter fragment directed weak lymphatic endothelial expression of the LacZ marker gene. This suggests that endothelial cell-specific elements occur in the proximal promoter, although further enhancer elements are probably located elsewhere. The sequence, organization, and variation in the VEGFR3 gene and its regulatory region provide important tools for the molecular genetic analysis of the lymphatic system and its disorders.

Notch alters VEGF responsiveness in human and murine endothelial cells by direct regulation of VEGFR-3 expression

“…The 5′UTR of the human VEGFR-3 gene contains multiple repetitive elements, making it difficult to amplify by PCR (ref. 28 and data not shown). Thus we chose primers that flank 3 CSL binding sites (-3818, -3687, and -3456) outside of the repetitive elements to amplify the precipitated DNA.…”

“…It has been suggested that the endothelial expression of VEGFR-3 is regulated at both the transcript and protein levels (28,29), yet little is known about these regulatory mechanisms. The portion of VEGFR-3 promoter that specifically drives expression of VEGFR-3 in BECs and LECs has been previously described (28). We identified 3 CSL consensus sequences (-747, -574, and -565) in this same VEGFR-3 regulatory region (Figure 2A).…”

“…In breast carcinomas, VEGFR-3 expression was upregulated in the endothelium of tumor blood vessels, while VEGF-C was expressed in the intraductal and invasive cancer cells (26,27), supporting a role for VEGFR-3 in tumor angiogenesis as well as lymphangiogenesis. The promoter of the VEGFR-3 gene contains elements that drive VEGFR-3 expression specifically to blood endothelial cells (BECs) and lymphatic endothelial cells (LECs) (28). However, little is known of the mechanisms that regulate expression of VEGFR-3.…”

A model for gene therapy of human hereditary lymphedema

“…To identify the Vegfr3 intron͞ exon boundaries, we aligned the Vegfr3 cDNA sequence (Accession no. L07296) with the VEGFR3 genomic sequence (17), and amplified exons 16 through 26 of Vegfr3, which were then sequenced from the C3H, B6, BALB͞c, BbxD2, and PES strains. We used the K14-VEGF-C156S and Vegfr3 ϩ/Ϫ mice in the crosses (10,12).…”

Mechanisms of HBx Mediated Liver Cancer: Multiple Pathways and Opportunities

“…Vascular endothelial growth factor receptor 3 (VEGFR-3), which is associated with angiogenesis, is a receptor tyrosine kinase that is expressed in lymphatic endothelial cells (Iljin et al, 2001). Binding of VEGFR-3 to the ligands VEGF-C or VEGF-D stimulate lymphangiogenesis (Alitalo & Carmeliet, 2002), while in carcinogenesis, the production of VEGFs by tumors promote metastases and result in decreased survival (Su et al, 2006).…”