title: Podocyte-specific deletion of Myh9 encoding nonmuscle myosin heavy chain 2A predisposes mice to glomerulopathy.
abstract: Genome-wide association studies linked single-nucleotide polymorphisms (SNPs) at the MYH9 locus to chronic kidney disease among African-Americans, particularly glomerular diseases such as HIV nephropathy and idiopathic focal and segmental glomerulosclerosis (FSGS). However, these MYH9 SNPs are intronic, and despite extensive sequencing, a causal variant remains elusive. To investigate the role of MYH9 in kidney disease, we selectively deleted Myh9 from mouse podocytes and found that mutant C57BL/6 mice did not develop renal insufficiency or proteinuria compared to control littermates, even when the mice were aged for 9 months. To explain the surprisingly normal phenotype, we considered genetic redundancy with the paralog Myh10 in podocytes, but we found that Myh10 was not expressed in podocytes in Myh9-deficient or control mice. We tested whether Myh9 podocyte deletion predisposed mice to glomerulopathy in response to injury by doxorubicin hydrochloride (Adriamycin), and we found that Myh9 podocyte-deleted mice developed proteinuria and glomerulosclerosis, while control mice were resistant. In summary, Myh9 podocyte deletion in C57BL/6 mice results in susceptibility to experimental doxorubicin hydrochloride glomerulopathy. We review evidence that MYH9 dysfunction in humans results in similar susceptibility and place our data, the first examination of Myh9 kidney disease in experimental animals, in the context of recent findings in human kidney disease, including the role of APOL1.
authors.affiliation: Renal, Electrolyte and Hypertension Division, University of Pennsylvania School of Medicine, 380 South University Ave., Philadelphia, PA 19104-4539, USA.
authors.forename: Duncan B
authors.initials: DB
authors.lastname: Johnstone
authors.forename: Jidong
authors.initials: J
authors.lastname: Zhang
authors.forename: Britta
authors.initials: B
authors.lastname: George
authors.forename: Catherine
authors.initials: C
authors.lastname: Léon
authors.forename: Christian
authors.initials: C
authors.lastname: Gachet
authors.forename: Hetty
authors.initials: H
authors.lastname: Wong
authors.forename: Rulan
authors.initials: R
authors.lastname: Parekh
authors.forename: Lawrence B
authors.initials: LB
authors.lastname: Holzman
mesh_terms: D000818:Animals; D000075944:Apolipoprotein L1; D001053:Apolipoproteins / Q000235:genetics; D002460:Cell Line; D004317:Doxorubicin / Q000008:administration & dosage; D020022:Genetic Predisposition to Disease; D005923:Glomerulosclerosis, Focal Segmental / Q000235:genetics; D006801:Humans; D007674:Kidney Diseases / Q000139:chemically induced / Q000235:genetics*; D008075:Lipoproteins, HDL / Q000235:genetics; D051379:Mice; D008810:Mice, Inbred C57BL; D009154:Mutation; D018995:Myosin Heavy Chains / Q000235:genetics* / Q000502:physiology; D024507:Nonmuscle Myosin Type IIA / Q000235:genetics* / Q000502:physiology*; D024501:Nonmuscle Myosin Type IIB / Q000235:genetics / Q000502:physiology; D050199:Podocytes; D011507:Proteinuria / Q000235:genetics; D017384:Sequence Deletion
chemical_list: C108666:APOL1 protein, human; D000075944:Apolipoprotein L1; D001053:Apolipoproteins; D008075:Lipoproteins, HDL; C525088:Myh9 protein, mouse; D004317:Doxorubicin; D024507:Nonmuscle Myosin Type IIA; D024501:Nonmuscle Myosin Type IIB; C103815:nonmuscle myosin type IIB heavy chain; D018995:Myosin Heavy Chains