The DUX4 gene at the FSHD1A locus encodes a pro-apoptotic protein.
Facioscapulohumeral muscular dystrophy (FSHD) patients carry contractions of the D4Z4-tandem repeat array on chromosome 4q35. Decrease in D4Z4 copy number is thought to alter a chromatin structure and activate expression of neighboring genes. D4Z4 contains a putative double-homeobox gene called DUX4. We identified DUX4 mRNAs in cells transfected with genomic fragments containing the DUX4 gene. Using RT-PCR we also recognized expressed DUX4 mRNAs in primary FSHD myoblasts. Polyclonal antibodies raised against specific DUX4 peptides detected the DUX4 protein in cells transfected with D4Z4 elements. DUX4 localizes in the nucleus of cells transfected with CMV-DUX4 expression vectors. A DUX4-related protein is endogenously expressed in nuclei of adult and fetal human rhabdomyosarcoma cell lines. Overexpression of DUX4 induces cell death, induces caspase 3/7 activity and alters emerin distribution at the nuclear envelope. We propose that DUX4-mediated cell death contributes to the pathogenic pathway in FSHD.
Kowaljow
Valeria
V
Laboratorio de Neurogenética, Instituto de Investigación, Médica Mercedes y Martín Ferreyra (INIMEC-CONICET), Córdoba, Argentina.
Marcowycz
Aline
A
Ansseau
Eugénie
E
Conde
Cecilia B
CB
Sauvage
Sébastien
S
Mattéotti
Christel
C
Arias
Cristina
C
Corona
E Daniel
ED
Nuñez
Nicolás G
NG
Leo
Oberdan
O
Wattiez
Ruddy
R
Figlewicz
Denise
D
Laoudj-Chenivesse
Dalila
D
Belayew
Alexandra
A
Coppée
Frédérique
F
Rosa
Alberto L
AL
D000595:Amino Acid Sequence; D017209:Apoptosis / Q000502:physiology*; D045744:Cell Line, Tumor; D015870:Gene Expression / Q000502:physiology; D018398:Homeodomain Proteins / Q000235:genetics* / Q000378:metabolism; D006801:Humans; D008565:Membrane Proteins / Q000378:metabolism; D008969:Molecular Sequence Data; D032342:Muscle Cells / Q000166:cytology / Q000502:physiology*; D020391:Muscular Dystrophy, Facioscapulohumeral / Q000235:genetics* / Q000473:pathology* / Q000503:physiopathology; D009685:Nuclear Envelope / Q000378:metabolism; D009687:Nuclear Proteins / Q000378:metabolism; D052097:Quadriceps Muscle / Q000166:cytology; D012333:RNA, Messenger / Q000378:metabolism; D012208:Rhabdomyosarcoma; D014158:Transcription, Genetic / Q000502:physiology
C121257:DUX4L1 protein, human; D018398:Homeodomain Proteins; D008565:Membrane Proteins; D009687:Nuclear Proteins; D012333:RNA, Messenger; C092710:emerin