title: Allelic Variants in Arhgef11 via the Rho-Rock Pathway Are Linked to Epithelial-Mesenchymal Transition and Contributes to Kidney Injury in the Dahl Salt-Sensitive Rat.
abstract: Previously, genetic analyses identified that variants in Arhgef11 may influence kidney injury in the Dahl salt-sensitive (S) rat, a model of hypertensive chronic kidney disease. To understand the potential mechanism by which altered expression and/or protein differences in Arhgef11 could play a role in kidney injury, stably transduced Arhgef11 knockdown cell lines as well as primary cultures of proximal tubule cells were studied. Genetic knockdown of Arhgef11 in HEK293 and NRK resulted in reduced RhoA activity, decreased activation of Rho-ROCK pathway, and less stress fiber formation versus control, similar to what was observed by pharmacological inhibition (fasudil). Primary proximal tubule cells (PTC) cultured from the S exhibited increased expression of Arhgef11, increased RhoA activity, and up regulation of Rho-ROCK signaling compared to control (small congenic). The cells were also more prone (versus control) to TGFβ-1 induced epithelial-mesenchymal transition (EMT), a hallmark feature of the development of renal interstitial fibrosis, and characterized by development of spindle shape morphology, gene expression changes in EMT markers (Col1a3, Mmp9, Bmp7, and Ocln) and increased expression of N-Cadherin and Vimentin. S derived PTC demonstrated a decreased ability to uptake FITC-albumin compared to the small congenic in vitro, which was confirmed by assessment of albumin re-uptake in vivo by infusion of FITC-albumin and immunofluorescence imaging. In summary, these studies suggest that genetic variants in the S form of Arhgef11 via increased expression and/or protein activity play a role in promoting kidney injury in the S rat through changes in cell morphology (Rho-Rock and/or EMT) that impact the function of tubule cells.
authors.affiliation: Department of Pharmacology and Toxicology, University of Mississippi Medical Center, Jackson, MS, United States of America.
authors.forename: Zhen
authors.initials: Z
authors.lastname: Jia
authors.affiliation: Department of Pharmacology and Toxicology, University of Mississippi Medical Center, Jackson, MS, United States of America.
authors.forename: Ashley C
authors.initials: AC
authors.lastname: Johnson
authors.affiliation: Department of Pharmacology and Toxicology, University of Mississippi Medical Center, Jackson, MS, United States of America.
authors.forename: Xuexiang
authors.initials: X
authors.lastname: Wang
authors.affiliation: Department of Pharmacology and Toxicology, University of Mississippi Medical Center, Jackson, MS, United States of America; Molecular and Genomics Core Facility, University of Mississippi Medical Center, Jackson, MS, United States of America.
authors.forename: Zibiao
authors.initials: Z
authors.lastname: Guo
authors.affiliation: Department of Medicine (Nephrology), University of Mississippi Medical Center, Jackson, MS, United States of America.
authors.forename: Albert W
authors.initials: AW
authors.lastname: Dreisbach
authors.affiliation: Department of Pathology, University of Mississippi Medical Center, Jackson, MS, United States of America.
authors.forename: Jack R
authors.initials: JR
authors.lastname: Lewin
authors.affiliation: Department of Pathology, University of Mississippi Medical Center, Jackson, MS, United States of America.
authors.forename: Patrick B
authors.initials: PB
authors.lastname: Kyle
authors.affiliation: Department of Pharmacology and Toxicology, University of Mississippi Medical Center, Jackson, MS, United States of America; Department of Medicine (Nephrology), University of Mississippi Medical Center, Jackson, MS, United States of America.
authors.forename: Michael R
authors.initials: MR
authors.lastname: Garrett
mesh_terms: D000483:Alleles; D000818:Animals; D020296:Animals, Congenic; D002460:Cell Line; D004195:Disease Models, Animal; D058750:Epithelial-Mesenchymal Transition / Q000235:genetics / Q000502:physiology; D055785:Gene Knockdown Techniques; D014644:Genetic Variation; D020662:Guanine Nucleotide Exchange Factors / Q000037:antagonists & inhibitors / Q000235:genetics* / Q000378:metabolism*; D057809:HEK293 Cells; D006801:Humans; D007687:Kidney Tubules, Proximal / Q000378:metabolism / Q000473:pathology; D008297:Male; D051179:Plakins / Q000378:metabolism; D051381:Rats; D020303:Rats, Inbred Dahl; D011918:Rats, Inbred SHR; D051436:Renal Insufficiency, Chronic / Q000235:genetics* / Q000378:metabolism / Q000473:pathology; D064067:Rho Guanine Nucleotide Exchange Factors / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism; D015398:Signal Transduction; D020741:rho GTP-Binding Proteins / Q000378:metabolism; D054460:rho-Associated Kinases / Q000378:metabolism
chemical_list: C577234:ARHGEF11 protein, human; C577237:Arhgef11 protein, rat; D020662:Guanine Nucleotide Exchange Factors; D051179:Plakins; D064067:Rho Guanine Nucleotide Exchange Factors; D054460:rho-Associated Kinases; D020741:rho GTP-Binding Proteins