title: DNAH6 and Its Interactions with PCD Genes in Heterotaxy and Primary Ciliary Dyskinesia.
abstract: Heterotaxy, a birth defect involving left-right patterning defects, and primary ciliary dyskinesia (PCD), a sinopulmonary disease with dyskinetic/immotile cilia in the airway are seemingly disparate diseases. However, they have an overlapping genetic etiology involving mutations in cilia genes, a reflection of the common requirement for motile cilia in left-right patterning and airway clearance. While PCD is a monogenic recessive disorder, heterotaxy has a more complex, largely non-monogenic etiology. In this study, we show mutations in the novel dynein gene DNAH6 can cause heterotaxy and ciliary dysfunction similar to PCD. We provide the first evidence that trans-heterozygous interactions between DNAH6 and other PCD genes potentially can cause heterotaxy. DNAH6 was initially identified as a candidate heterotaxy/PCD gene by filtering exome-sequencing data from 25 heterotaxy patients stratified by whether they have airway motile cilia defects. dnah6 morpholino knockdown in zebrafish disrupted motile cilia in Kupffer's vesicle required for left-right patterning and caused heterotaxy with abnormal cardiac/gut looping. Similarly DNAH6 shRNA knockdown disrupted motile cilia in human and mouse respiratory epithelia. Notably a heterotaxy patient harboring heterozygous DNAH6 mutation was identified to also carry a rare heterozygous PCD-causing DNAI1 mutation, suggesting a DNAH6/DNAI1 trans-heterozygous interaction. Furthermore, sequencing of 149 additional heterotaxy patients showed 5 of 6 patients with heterozygous DNAH6 mutations also had heterozygous mutations in DNAH5 or other PCD genes. We functionally assayed for DNAH6/DNAH5 and DNAH6/DNAI1 trans-heterozygous interactions using subthreshold double-morpholino knockdown in zebrafish and showed this caused heterotaxy. Similarly, subthreshold siRNA knockdown of Dnah6 in heterozygous Dnah5 or Dnai1 mutant mouse respiratory epithelia disrupted motile cilia function. Together, these findings support an oligogenic disease model with broad relevance for further interrogating the genetic etiology of human ciliopathies.
authors.affiliation: Department of Developmental Biology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, United States of America.
authors.forename: You
authors.initials: Y
authors.lastname: Li
authors.affiliation: Department of Developmental Biology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, United States of America.
authors.forename: Hisato
authors.initials: H
authors.lastname: Yagi
authors.affiliation: Department of Developmental Biology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, United States of America.
authors.forename: Ezenwa Obi
authors.initials: EO
authors.lastname: Onuoha
authors.affiliation: Department of Developmental Biology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, United States of America.
authors.forename: Rama Rao
authors.initials: RR
authors.lastname: Damerla
authors.affiliation: Department of Developmental Biology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, United States of America.
authors.forename: Richard
authors.initials: R
authors.lastname: Francis
authors.affiliation: Division of Pediatric Cardiology, Tokyo Women's Medical University, Tokyo, Japan.
authors.forename: Yoshiyuki
authors.initials: Y
authors.lastname: Furutani
authors.affiliation: Departments of Pediatrics and Medical and Molecular Genetics, Indiana University School of Medicine, Indianapolis, Indiana, United States of America.
authors.forename: Muhammad
authors.initials: M
authors.lastname: Tariq
authors.affiliation: University of Connecticut Health Center, Farmington, Connecticut, United States of America.
authors.forename: Stephen M
authors.initials: SM
authors.lastname: King
authors.affiliation: The Core Electron Microscopy Facility, University of Massachusetts Medical School, Worcester, Massachusetts, United States of America.
authors.forename: Gregory
authors.initials: G
authors.lastname: Hendricks
authors.affiliation: Department of Developmental Biology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, United States of America.
authors.forename: Cheng
authors.initials: C
authors.lastname: Cui
authors.affiliation: Department of Developmental Biology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, United States of America.
authors.forename: Manush
authors.initials: M
authors.lastname: Saydmohammed
authors.affiliation: Department of Developmental Biology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, United States of America.
authors.forename: Dong Min
authors.initials: DM
authors.lastname: Lee
authors.affiliation: Department of Developmental Biology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, United States of America.
authors.forename: Maliha
authors.initials: M
authors.lastname: Zahid
authors.affiliation: Department of Pulmonary and Sleep Medicine, Children's National Medical Center, Washington, D.C., United States of America.
authors.forename: Iman
authors.initials: I
authors.lastname: Sami
authors.affiliation: Department of Cardiology, Children's National Medical Center, Washington, D.C., United States of America.
authors.forename: Linda
authors.initials: L
authors.lastname: Leatherbury
authors.affiliation: Program in Molecular Medicine, University of Massachusetts Medical School, Worcester, Massachusetts, United States of America.
authors.forename: Gregory J
authors.initials: GJ
authors.lastname: Pazour
authors.affiliation: Departments of Pediatrics and Medical and Molecular Genetics, Indiana University School of Medicine, Indianapolis, Indiana, United States of America.
authors.forename: Stephanie M
authors.initials: SM
authors.lastname: Ware
authors.affiliation: Division of Pediatric Cardiology, Tokyo Women's Medical University, Tokyo, Japan.
authors.forename: Toshio
authors.initials: T
authors.lastname: Nakanishi
authors.affiliation: Department of Pediatrics, University of Pennsylvania Perelman School of Medicine, Division of Cardiology, Children's Hospital of Philadelphia, Philadelphia, Pennsylvania, United States of America.
authors.forename: Elizabeth
authors.initials: E
authors.lastname: Goldmuntz
authors.affiliation: Department of Developmental Biology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, United States of America.
authors.forename: Michael
authors.initials: M
authors.lastname: Tsang
authors.affiliation: Department of Developmental Biology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, United States of America.
authors.forename: Cecilia W
authors.initials: CW
authors.lastname: Lo
mesh_terms: D000818:Animals; D056444:Axonemal Dyneins / Q000235:genetics / Q000378:metabolism; D019521:Body Patterning; D002923:Cilia / Q000502:physiology; D004625:Embryo, Nonmammalian; D055785:Gene Knockdown Techniques; D059446:Heterotaxy Syndrome / Q000235:genetics*; D006579:Heterozygote; D006801:Humans; D007619:Kartagener Syndrome / Q000235:genetics*; D007728:Kupffer Cells / Q000473:pathology; D018345:Mice, Knockout; D009154:Mutation; D034741:RNA, Small Interfering / Q000235:genetics; D015027:Zebrafish / Q000196:embryology / Q000235:genetics; D029961:Zebrafish Proteins / Q000235:genetics / Q000378:metabolism
chemical_list: C425071:DNAI1 protein, human; D034741:RNA, Small Interfering; D029961:Zebrafish Proteins; D056444:Axonemal Dyneins; C497507:DNAH5 protein, human