Transcriptional Regulation of PDGF-A and TGF-β by +KTS WT1 Deletion Mutants and a Mutant Mimicking Denys-Drash Syndrome

Denys-Drash syndrome (DDS) and Frasier syndrome (FS) are rare diseases caused by the mutations of Wilms tumor gene, WT1 The common denominator in these syndromes is a nephropathy, which is manifested by early-onset proteinuria, nephrotic syndrome and end stage renal failure. Although these syndromes are genetic models of nephropathy and the mutations of WT1 gene are characterized in these patients, the mechanism how mutations of WT1 gene affect the embryonic, kidney adversely has not been elucidated. Recently, there was a report that FS is caused by mutations in the donor splice site of WT1. These mutations predicted loss of +KTS isoform, which is one of the jour splicing variants of WT1. In this study, two +KTS deletion mutants of WT1 were made as well as a WT1 mutant mimicking a mutation found in a patient who had diffuse mesangial sclerosis, end stage renal failure and Wilms tumor. Mutant embryonic kidncy cell lines were established by transfection of 293 embryonic kidney cells with WT1 mutants. We inv...