Description: Homo sapiens DEAD (Asp-Glu-Ala-Asp) box helicase 21 (DDX21), transcript variant 1, mRNA. RefSeq Summary (NM_004728): DEAD box proteins, characterized by the conserved motif Asp-Glu-Ala-Asp (DEAD), are putative RNA helicases. They are implicated in a number of cellular processes involving alteration of RNA secondary structure such as translation initiation, nuclear and mitochondrial splicing, and ribosome and spliceosome assembly. Based on their distribution patterns, some members of this family are believed to be involved in embryogenesis, spermatogenesis, and cellular growth and division. This gene encodes a DEAD box protein, which is an antigen recognized by autoimmune antibodies from a patient with watermelon stomach disease. This protein unwinds double-stranded RNA, folds single-stranded RNA, and may play important roles in ribosomal RNA biogenesis, RNA editing, RNA transport, and general transcription. [provided by RefSeq, Jul 2008]. Transcript (Including UTRs) Position: hg19 chr10:70,715,879-70,744,825 Size: 28,947 Total Exon Count: 15 Strand: + Coding Region Position: hg19 chr10:70,715,982-70,742,568 Size: 26,587 Coding Exon Count: 15
ID:DDX21_HUMAN DESCRIPTION: RecName: Full=Nucleolar RNA helicase 2; EC=3.6.4.13; AltName: Full=DEAD box protein 21; AltName: Full=Gu-alpha; AltName: Full=Nucleolar RNA helicase Gu; AltName: Full=Nucleolar RNA helicase II; AltName: Full=RH II/Gu; FUNCTION: Can unwind double-stranded RNA (helicase) and can fold or introduce a secondary structure to a single-stranded RNA (foldase). Functions as cofactor for JUN-activated transcription. Involved in rRNA processing. CATALYTIC ACTIVITY: ATP + H(2)O = ADP + phosphate. SUBUNIT: Component of the B-WICH complex, at least composed of SMARCA5/SNF2H, BAZ1B/WSTF, SF3B1, DEK, MYO1C, ERCC6, MYBBP1A and DDX21. SUBCELLULAR LOCATION: Nucleus, nucleolus. DOMAIN: The two enzymatic activities reside in two separate domains, the helicase in the N-terminus and the foldase in the C- terminus. DOMAIN: The 3 X 5 AA repeats seem to be critical for the RNA folding activity (By similarity). MISCELLANEOUS: Autoantibodies against DDX21 are found in patients with watermelon stomach disease, which is characterized by prominent stripes of ectatic vascular tissue in the stomach similar to stripes on a watermelon. SIMILARITY: Belongs to the DEAD box helicase family. DDX21/DDX50 subfamily. SIMILARITY: Contains 1 helicase ATP-binding domain. SIMILARITY: Contains 1 helicase C-terminal domain. SEQUENCE CAUTION: Sequence=AAB02546.1; Type=Erroneous initiation;
The RNAfold program from the Vienna RNA Package is used to perform the secondary structure predictions and folding calculations. The estimated folding energy is in kcal/mol. The more negative the energy, the more secondary structure the RNA is likely to have.
ModBase Predicted Comparative 3D Structure on Q9NR30
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Orthologous Genes in Other Species
Orthologies between human, mouse, and rat are computed by taking the best BLASTP hit, and filtering out non-syntenic hits. For more distant species reciprocal-best BLASTP hits are used. Note that the absence of an ortholog in the table below may reflect incomplete annotations in the other species rather than a true absence of the orthologous gene.
US Server
Sequence and Links to Tools and Databases 
Common Gene Haplotype Alleles 
