Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P43146 (tumour suppressor)
 5,935 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Aberrations in the WT1 tumour suppressor gene have been documented in a fraction of Wilms' tumours (WTs). Encoding a protein with four zinc fingers, the WT1 gene is expressed in the developing kidney, gonads, uterus, spleen, mesothelium and brain. Using polymerase chain reaction (PCR), single strand conformation polymorphism (SSCP) analysis and direct DNA sequencing, we analysed 156 diverse tumours for abnormalities of zinc finger 3 (ZF3), a mutational hotspot in WT1. Only one sample (WT) exhibited PCR-SSCP mobility shift. A CGA to TGA nonsense mutation at codon 390 with arginine being substituted with a stop codon was detected and predicted to encode a faulty WT1 protein in this WT, out of 8 WTs studied. Our results are consistent with the presence of WT1 ZF3 mutations in a subset of WTs, but not in other tumours of urogenital nor of WT1-related origin.
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PMID:The third zinc finger of the WT1 gene is mutated in Wilms' tumour but not in a broad range of other urogenital tumours. 823 37

Cytomegalovirus-based mammalian expression vectors are widely used to drive the expression of transfected genes in cultured cells. Immunofluorescent staining of the WT1 protein in 3T3 and 293 cell clones, stably transfected with a cyomegalovirus (CMV) expression vector carrying a cDNA coding for the tumour suppressor protein WT1, showed extreme cell to cell variation in the amount of recombinant protein expressed, indicative of cell cycle dependence. This was investigated further by Western blot and FACS analysis which showed that WT1 protein expression was highest in S phase and almost absent in G0/G1. Northern blot analysis of cell clones expressing sense or antisense WT1 cDNAs regulated by the CMV promoter/enhancer showed that RNA expression was also cell cycle-dependent. Western blotting of cells expressing a luciferase reporter gene driven by the CMV promoter/enhancer also showed apparent cell cycle-dependent expression. We further demonstrated that the expression of these gene constructs was serum responsive with a 10-fold increase in expression occurring 2 h after the addition of serum. These results show that the CMV promoter/enhancer system varied in its response to serum and the cell cycle state. Therefore, care must be taken when interpreting any phenotypic alterations (or lack of them) produced in cells transfected with CMV-based expression vectors.
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PMID:Serum-dependent and cell cycle-dependent expression from a cytomegalovirus-based mammalian expression vector. 926 80

The Wilms' tumour suppressor gene (wt1) is mutated in a subset of patients with Wilms' tumour and has a critical role in urogenital development. wt1 encodes a zinc finger transcription factor which regulates expression of several genes involved in cellular proliferation and differentiation. Although a number of studies have characterized the DNA binding properties of the WT1 protein, recent evidence has suggested that WT1 may also have a role in RNA metabolism. We have used an RNA selection method to identify WT1 binding ligands from a random RNA pool. Three groups of RNA ligands specifically recognized by WT1 were identified. Mutational analysis pinpointed ribonucleotide sequences critical for binding. Analysis of truncated WT1 proteins demonstrated that three of four zinc fingers were necessary for RNA-protein interaction. The naturally occurring WT1 isoforms with insertion of lysine, threonine and serine between zinc fingers three and four were unable to bind the selected RNAs. The selected RNA ligands competed with the cognate WT1 DNA binding site for complex formation with WT1. Our findings suggest potential cellular RNA target sequences for WT1 and provide tools for studying the structural and functional properties of this tumour suppressor protein.
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PMID:Overlapping RNA and DNA binding domains of the wt1 tumor suppressor gene product. 951 53

The Wilms' tumour suppressor gene, WT1, encodes a zinc-finger protein that is mutated in Wilms' tumours and other malignancies. WT1 is one of the earliest genes expressed during kidney development. WT1 proteins can activate and repress putative target genes in vitro, although the in vivo relevance of such target genes often remains unverified. To better understand the role of WT1 in tumorigenesis and kidney development, we need to identify downstream target genes. In this study, we have expression profiled human embryonic kidney 293 cells stably transfected to allow inducible WT1 expression and mouse mesonephric M15 cells transfected with a WT1 antisense construct to abolish endogenous expression of all WT1 isoforms to identify WT1-responsive genes. The complementary overlap between the two cell lines revealed a pronounced repression of genes involved in cholesterol biosynthesis by WT1. This pathway is transcriptionally regulated by the sterol responsive element-binding proteins (SREBPs). Here, we provide evidence that the C-terminal end of the WT1 protein can directly interact with SREBP, suggesting that WT1 may modify the transcriptional function of SREBPs via a direct protein-protein interaction. Therefore, the tumour suppressor activities of WT1 may be achieved by repressing the mevalonate pathway, thereby controlling cellular proliferation and promoting terminal differentiation.
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PMID:Anlaysis of complementary expression profiles following WT1 induction versus repression reveals the cholesterol/fatty acid synthetic pathways as a possible major target of WT1. 1502 18