Mouse Dux is myotoxic and shares partial functional homology with its human paralog DUX4.
D4Z4 repeats are present in at least 11 different mammalian species, including humans and mice. Each repeat contains an open reading frame encoding a double homeodomain (DUX) family transcription factor. Aberrant expression of the D4Z4 ORF called DUX4 is associated with the pathogenesis of Facioscapulohumeral muscular dystrophy (FSHD). DUX4 is toxic to numerous cell types of different species, and over-expression caused dysmorphism and developmental arrest in frogs and zebrafish, embryonic lethality in transgenic mice, and lesions in mouse muscle. Because DUX4 is a primate-specific gene, questions have been raised about the biological relevance of over-expressing it in non-primate models, as DUX4 toxicity could be related to non-specific cellular stress induced by over-expressing a DUX family transcription factor in organisms that did not co-evolve its regulated transcriptional networks. We assessed toxic phenotypes of DUX family genes, including DUX4, DUX1, DUX5, DUXA, DUX4-s, Dux-bl and mouse Dux. We found that DUX proteins were not universally toxic, and only the mouse Dux gene caused similar toxic phenotypes as human DUX4. Using RNA-seq, we found that 80% of genes upregulated by Dux were similarly increased in DUX4-expressing cells. Moreover, 43% of Dux-responsive genes contained ChIP-seq binding sites for both Dux and DUX4, and both proteins had similar consensus binding site sequences. These results suggested DUX4 and Dux may regulate some common pathways, and despite diverging from a common progenitor under different selective pressures for millions of years, the two genes maintain partial functional homology.
Center for Gene Therapy, The Research Institute at Nationwide Children's Hospital, Columbus, OH, USA.
Jocelyn O
JO
Eidahl
Center for Gene Therapy, The Research Institute at Nationwide Children's Hospital, Columbus, OH, USA.|Biomedical Sciences Graduate Program, The Ohio State University, Columbus, OH, USA
Carlee R
CR
Giesige
Center for Gene Therapy, The Research Institute at Nationwide Children's Hospital, Columbus, OH, USA.
Jacqueline S
JS
Domire
Center for Gene Therapy, The Research Institute at Nationwide Children's Hospital, Columbus, OH, USA.
Lindsay M
LM
Wallace
Center for Gene Therapy, The Research Institute at Nationwide Children's Hospital, Columbus, OH, USA.
Allison M
AM
Fowler
Center for Gene Therapy, The Research Institute at Nationwide Children's Hospital, Columbus, OH, USA.
Susan M
SM
Guckes
Center for Gene Therapy, The Research Institute at Nationwide Children's Hospital, Columbus, OH, USA.
Sara E
SE
Garwick-Coppens
Active Motif, Carlsbad, CA, USA.
Paul
P
Labhart
Center for Gene Therapy, The Research Institute at Nationwide Children's Hospital, Columbus, OH, USA.|Biomedical Sciences Graduate Program, The Ohio State University, Columbus, OH, USA|Department of Pediatrics, The Ohio State University, Columbus, OH, USA
Scott Q
SQ
Harper
D000595:Amino Acid Sequence; D000818:Animals; D002460:Cell Line; D047369:Chromatin Immunoprecipitation; D019143:Evolution, Molecular; D053263:Gene Regulatory Networks; D018398:Homeodomain Proteins / Q000235:genetics / Q000378:metabolism*; D006801:Humans; D051379:Mice; D008822:Mice, Transgenic; D020391:Muscular Dystrophy, Facioscapulohumeral / Q000378:metabolism; D009183:Mycotoxins / Q000235:genetics / Q000378:metabolism*; D032446:Myoblasts / Q000378:metabolism*; D016415:Sequence Alignment; D017423:Sequence Analysis, RNA
C121257:DUX4L1 protein, human; D018398:Homeodomain Proteins; D009183:Mycotoxins