title: Loss-of-function mutations in the RNA biogenesis factor NAF1 predispose to pulmonary fibrosis-emphysema.
abstract: Chronic obstructive pulmonary disease and pulmonary fibrosis have been hypothesized to represent premature aging phenotypes. At times, they cluster in families, but the genetic basis is not understood. We identified rare, frameshift mutations in the gene for nuclear assembly factor 1, NAF1, a box H/ACA RNA biogenesis factor, in pulmonary fibrosis-emphysema patients. The mutations segregated with short telomere length, low telomerase RNA levels, and extrapulmonary manifestations including myelodysplastic syndrome and liver disease. A truncated NAF1 was detected in cells derived from patients, and, in cells in which the frameshift mutation was introduced by genome editing, telomerase RNA levels were reduced. The mutant NAF1 lacked a conserved carboxyl-terminal motif, which we show is required for nuclear localization. To understand the disease mechanism, we used CRISPR (clustered regularly interspaced short palindromic repeats)/Cas9 (CRISPR-associated protein-9 nuclease) to generate Naf1(+/-) mice and found that they had half the levels of telomerase RNA. Other box H/ACA RNA levels were also decreased, but rRNA pseudouridylation, which is guided by snoRNAs, was intact. Moreover, first-generation Naf1(+/-) mice showed no evidence of ribosomal pathology. Our data indicate that disease in NAF1 mutation carriers is telomere-mediated; they show that NAF1 haploinsufficiency selectively disturbs telomere length homeostasis by decreasing the levels of telomerase RNA while sparing rRNA pseudouridylation.
authors: Department of Oncology, Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA. Medical Scientist Training Program, Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA.
authors: Susan E
authors: SE
authors: Stanley
authors: Department of Oncology, Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA. Medical Scientist Training Program, Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA.
authors: Dustin L
authors: DL
authors: Gable
authors: Department of Oncology, Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA.
authors: Christa L
authors: CL
authors: Wagner
authors: Department of Biology, Massachusetts Institute of Technology, Cambridge, MA 02139, USA.
authors: Thomas M
authors: TM
authors: Carlile
authors: Department of Oncology, Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA.
authors: Vidya Sagar
authors: VS
authors: Hanumanthu
authors: Department of Chemistry and Biochemistry, Arizona State University, Tempe, AZ 85277, USA.
authors: Joshua D
authors: JD
authors: Podlevsky
authors: Department of Oncology, Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA.
authors: Sara E
authors: SE
authors: Khalil
authors: Department of Oncology, Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA. Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA. Sidney Kimmel Comprehensive Cancer Center, Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA.
authors: Amy E
authors: AE
authors: DeZern
authors: Department of Biology, Massachusetts Institute of Technology, Cambridge, MA 02139, USA.
authors: Maria F
authors: MF
authors: Rojas-Duran
authors: Department of Oncology, Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA. Sidney Kimmel Comprehensive Cancer Center, Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA. McKusick-Nathans Institute of Genetic Medicine, Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA.
authors: Carolyn D
authors: CD
authors: Applegate
authors: Department of Oncology, Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA.
authors: Jonathan K
authors: JK
authors: Alder
authors: Department of Oncology, Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA. Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA.
authors: Erin M
authors: EM
authors: Parry
authors: Department of Biology, Massachusetts Institute of Technology, Cambridge, MA 02139, USA.
authors: Wendy V
authors: WV
authors: Gilbert
authors: Department of Oncology, Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA. Sidney Kimmel Comprehensive Cancer Center, Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA. McKusick-Nathans Institute of Genetic Medicine, Johns Hopkins University School of Medicine, Baltimore, MD 21287, USA. marmani1@jhmi.edu.
authors: Mary
authors: M
authors: Armanios
mesh_terms: D000818:Animals; D000071183:Autophagy-Related Proteins; D002352:Carrier Proteins / Q000235:genetics; D004646:Emphysema / Q000235:genetics*; D020022:Genetic Predisposition to Disease / Q000235:genetics; D059014:High-Throughput Nucleotide Sequencing; D006801:Humans; D015151:Immunoblotting; D051379:Mice; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D009154:Mutation / Q000235:genetics; D009419:Nerve Tissue Proteins / Q000235:genetics; D011658:Pulmonary Fibrosis / Q000235:genetics*; D012313:RNA / Q000235:genetics*; D012261:Ribonucleoproteins / Q000235:genetics; D019098:Telomerase / Q000235:genetics; D016615:Telomere / Q000235:genetics
chemical_list: D000071183:Autophagy-Related Proteins; D002352:Carrier Proteins; C551999:NAF1 protein, human; D009419:Nerve Tissue Proteins; C515811:Noxp70 protein, mouse; D012261:Ribonucleoproteins; C422952:telomerase RNA; D012313:RNA; D019098:Telomerase