Identification of a DNA- binding site and transcriptional target for the EWS-WT1(+KTS) oncoprotein Journal Article
| Authors: | Reynolds, P. A.; Smolen, G. A.; Palmer, R. E.; Sgroi, D.; Yajnik, V.; Gerald, W. L.; Haber, D. A. |
| Article Title: | Identification of a DNA- binding site and transcriptional target for the EWS-WT1(+KTS) oncoprotein |
| Abstract: | Desmoplastic small round cell tumor (DSRCT) is defined by a chimeric transcription factor, resulting from fusion of the N-terminal domain of the Ewing's sarcoma gene EWS to the three C-terminal zinc fingers of the Wilms' tumor suppressor WT1. Although DNA-binding sites have been defined for the uninterrupted WT1 zinc finger domains, the most prevalent isoforms of both WT1 and EWS-WT1 have an insertion of three amino acids [lysine, threonine, and serine (KTS)], which abrogates binding to known consensus sequences and transactivation of known target genes. Here, we used cDNA subtractive hybridization to identify an endogenous gene, LRRC15, which is specifically up-regulated after inducible expression of EWS-WT1(+KTS) in cancer cell lines, and is expressed within primary DSRCT cells. The chimeric protein binds in vitro and in vivo to a specific element upstream of LRRC15, leading to dramatic transcriptional activation. Mutagenesis studies define the optimal binding site of the (+KTS) isoform of EWS-WT1 as 5′-GGAGG(A/G)-3′. LRRC15 encodes a leucine-rich transmembrane protein, present at the leading edge of migrating cells, the expression of which in normal tissues is restricted to the invasive cytotrophoblast layer of the placenta; small interfering (siRNA)-mediated suppression of LRRC15 expression in breast cancer cells leads to abrogation of invasiveness in vitro. Together, these observations define the consequence of (KTS) insertion within WT1-derived zinc fingers, and identify a novel EWS-WT1 transcriptional target implicated in tumor invasiveness. |
| Keywords: | controlled study; oncoprotein; human cell; gene; gene targeting; peritoneal neoplasms; breast cancer; gene expression; serine; carboxy terminal sequence; transcription initiation; protein binding; transcription factor; genetic transcription; ewing sarcoma; cancer invasion; dna; amino acid sequence; molecular sequence data; nucleotide sequence; gene repression; membrane protein; oncogene proteins, fusion; alternative splicing; transactivation; cell migration; binding site; threonine; binding sites; gene insertion; dna binding; zinc finger protein; invasion; mutagenesis; isoprotein; lysine; complementary dna; rna processing, post-transcriptional; nephroblastoma; desmoplastic small round cell tumor; chimeric protein; zinc finger motif; zinc finger; promoter; dna hybridization; ews gene; dsrct; ews-wt1; lrrc15 gene; wt1 gene; humans; human; priority journal; article; insertion sequences; cytotrophoblast |
| Journal Title: | Genes and Development |
| Volume: | 17 |
| Issue: | 17 |
| ISSN: | 0890-9369 |
| Publisher: | Cold Spring Harbor Laboratory Press |
| Date Published: | 2003-09-01 |
| Start Page: | 2094 |
| End Page: | 2107 |
| Language: | English |
| DOI: | 10.1101/gad.1110703 |
| PUBMED: | 12923058 |
| PROVIDER: | scopus |
| PMCID: | PMC196452 |
| DOI/URL: | |
| Notes: | Export Date: 12 September 2014 -- Source: Scopus |
