This gene is located within a D4Z4 macrosatellite repeat array in the subtelomeric regionofchromosome 4q35. The D4Z4 repeat array contains 11-150 D4Z4 repeats in the general population; a highly homologous D4Z4 repeat array has been identified on chromosome 10. The gene consists of three exons. Exons 1 and 2 are present in each D4Z4 repeat. Only one copy of exon 3 is present, telomeric to the D4Z4 repeat array.[4] The open reading frame (ORF) is entirely contained within exon 1 and contains two homeoboxes.[4] Exons 2 and 3 encode for the three prime untranslated region (3′-UTR).[4] In certain haplotypes, exon 3 contains a polyadenylation signal.[4] There was no evidence for transcription from standard cDNA libraries however RT-PCR and in-vitro expression experiments indicate that the ORF is transcribed.[5]
The repeat-array and ORF are conserved in other mammals.
The two homeodomains and TAD have well-defined tertiary structure.[4] The region between the second homeodomain and TAD is predicted to be disordered.[4]
DUX4 transcripts can be spliced to produce either DUX4-S (short) or DUX4-FL (full length) mRNAs. DUX4-FL mRNA encodes for the entire DUX4 protein. DUX4-S mRNA encodes for a partial DUX4 protein, which lacks the transcription-activating domain.[4]
DUX4 protein a transcriptional activator of many genes, one example being paired-like homeodomain transcription factor 1 (PITX1).[5] It likely stimulates zygotic genome activation.[citation needed]
The two homeodomains allow DUX4 protein to bind to DNA.[4] The C-terminal domain is involved in target gene activation.[4]
^"Human PubMed Reference:". National Center for Biotechnology Information, U.S. National Library of Medicine.
^Gabriëls J, Beckers MC, Ding H, De Vriese A, Plaisance S, van der Maarel SM, et al. (August 1999). "Nucleotide sequence of the partially deleted D4Z4 locus in a patient with FSHD identifies a putative gene within each 3.3 kb element". Gene. 236 (1): 25–32. doi:10.1016/S0378-1119(99)00267-X. PMID10433963.
