title: Expression of RASSF6 in kidney and the implication of RASSF6 and the Hippo pathway in the sorbitol-induced apoptosis in renal proximal tubular epithelial cells.
abstract: RASSF6, a member of RASSF tumour suppressor proteins, binds to mammalian Ste20-like kinases (MST1/2), core kinases of the proapoptotic Hippo pathway and cooperates with the Hippo pathway to induce apoptosis. We originally identified RASSF6 as a putative interactor of membrane-associated guanylate kinase inverted (MAGI)-1 by the yeast two-hybrid screening. We used human kidney cDNA library for the screening. MAGI-1 is abundantly expressed in kidney and is a core component of the slit diaphragm. These findings suggest that RASSF6 is expressed in kidney. However, the function of RASSF6 in kidney is not yet studied. We performed this study to confirm the interaction of RASSF6 with MAGI-1, to analyse the expression of RASSF6 in kidney and to gain insight into the function of RASSF6 in kidney. RASSF6 binds to PDZ domains of MAGI-1 through its C-terminal PDZ-binding motif and is coimmunoprecipitated with MAGI-1 from rat liver. RASSF6 is localized in normal kidney glomerulus but disappears when the slit diaphragm is disrupted in nephrotic kidney. RASSF6 is also localized on apical membranes in renal proximal tubular epithelial cells. We demonstrated that RASSF6 as well as the Hippo pathway are involved in the sorbitol-induced apoptosis in immortalized human proximal renal tubular epithelial HK-2 cells.
authors.affiliation: Department of Medical Biochemistry, Graduate School of Medicine, Tokyo Medical and Dental University, Tokyo 113-8519, Japan.
authors.forename: Kanchanamala
authors.initials: K
authors.lastname: Withanage
authors.forename: Kentaro
authors.initials: K
authors.lastname: Nakagawa
authors.forename: Mitsunobu
authors.initials: M
authors.lastname: Ikeda
authors.forename: Hidetake
authors.initials: H
authors.lastname: Kurihara
authors.forename: Takumi
authors.initials: T
authors.lastname: Kudo
authors.forename: Zeyu
authors.initials: Z
authors.lastname: Yang
authors.forename: Ayuko
authors.initials: A
authors.lastname: Sakane
authors.forename: Takuya
authors.initials: T
authors.lastname: Sasaki
authors.forename: Yutaka
authors.initials: Y
authors.lastname: Hata
mesh_terms: D000818:Animals; D017209:Apoptosis; D051017:Apoptosis Regulatory Proteins; D002460:Cell Line; D004847:Epithelial Cells / Q000378:metabolism*; D057809:HEK293 Cells; D006801:Humans; D007668:Kidney / Q000187:drug effects / Q000378:metabolism*; D007687:Kidney Tubules, Proximal / Q000378:metabolism*; D008297:Male; D008856:Microscopy, Fluorescence; D020559:Monomeric GTP-Binding Proteins / Q000235:genetics / Q000378:metabolism*; D054731:PDZ Domains; D017346:Protein Serine-Threonine Kinases / Q000378:metabolism*; D051381:Rats; D015398:Signal Transduction; D013012:Sorbitol / Q000494:pharmacology*
chemical_list: D051017:Apoptosis Regulatory Proteins; C519911:RASSF6 protein, human; D013012:Sorbitol; D017346:Protein Serine-Threonine Kinases; D020559:Monomeric GTP-Binding Proteins