{"product_id":"recombinant-human-nucleolar-rna-helicase-2-ddx21-bhp10514982","title":"Recombinant Human Nucleolar RNA helicase 2 (DDX21)","description":"\u003ch2\u003eOverview\u003c\/h2\u003e\u003cp\u003eRecombinant Human Nucleolar RNA helicase 2 (DDX21) is a recombinant protein preparation derived from Homo sapiens (Human). It is commonly used as a defined reagent for assay development, binding studies, and analytical controls where consistent protein specifications are required.\u003c\/p\u003e\u003ch2\u003eKey elements and design rationale\u003c\/h2\u003e\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eExpressed region:\u003c\/strong\u003e 1-783aa.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eExpression system:\u003c\/strong\u003e E.coli (may influence folding and post-translational modifications).\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eTag\/format:\u003c\/strong\u003e C-terminal 6xHis-tagged; Liquid or Lyophilized powder.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eExpected size:\u003c\/strong\u003e 94.2 kDa (as provided).\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003ePurity:\u003c\/strong\u003e Greater than 85% as determined by SDS-PAGE.\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003eRegion choice, expression system, and tag\/format can influence folding, post-translational modifications, and interaction behavior in downstream assays.\u003c\/p\u003e\u003ch2\u003eBiological background\u003c\/h2\u003e\u003cp\u003eRNA helicase that acts as a sensor of the transcriptional status of both RNA polymerase (Pol) I and II: promotes ribosomal RNA (rRNA) processing and transcription from polymerase II (Pol II). Binds various RNAs, such as rRNAs, snoRNAs, 7SK and, at lower extent, mRNAs. In the nucleolus, localizes to rDNA locus, where it directly binds rRNAs and snoRNAs, and promotes rRNA transcription, processing and modification. Required for rRNA 2'-O-methylation, possibly by promoting the recruitment of late-acting snoRNAs SNORD56 and SNORD58 with pre-ribosomal complexes. In the nucleoplasm, binds 7SK RNA and is recruited to the promoters of Pol II-transcribed genes: acts by facilitating the release of P-TEFb from inhibitory 7SK snRNP in a manner that is dependent on its helicase activity, thereby promoting transcription of its target genes. Functions as cofactor for JUN-activated transcription: required for phosphorylation of JUN at 'Ser-77'. Can unwind double-stranded RNA (helicase) and can fold or introduce a secondary structure to a single-stranded RNA (foldase). Together with SIRT7, required to prevent R-loop-associated DNA damage and transcription-associated genomic instability: deacetylation by SIRT7 activates the helicase activity, thereby overcoming R-loop-mediated stalling of RNA polymerases. Involved in rRNA processing. May bind to specific miRNA hairpins. Component of a multi-helicase-TICAM1 complex that acts as a cytoplasmic sensor of viral double-stranded RNA (dsRNA) and plays a role in the activation of a cascade of antiviral responses including the induction of pro-inflammatory cytokines via the adapter molecule TICAM1.\u003c\/p\u003e\u003ch2\u003eResearch relevance and current trends\u003c\/h2\u003e\u003cul\u003e\n\u003cli\u003eDomain- and isoform-aware assay design to improve biological interpretation across model systems.\u003c\/li\u003e\n\u003cli\u003eQuantitative workflows emphasizing calibration standards, spike-in controls, and cross-lot comparability.\u003c\/li\u003e\n\u003cli\u003eIn vitro binding\/kinetics profiling (SPR\/BLI) to connect biochemical interactions with cellular phenotypes.\u003c\/li\u003e\n\u003c\/ul\u003e\u003ch2\u003eCommon research applications\u003c\/h2\u003e\u003cul\u003e\n\u003cli\u003ePrepare aliquots of DDX21 for reproducible in vitro assays (minimize freeze–thaw).\u003c\/li\u003e\n\u003cli\u003eUse DDX21 as a calibration standard in quantitative assays (standard curve setup).\u003c\/li\u003e\n\u003cli\u003eMeasure binding interactions to DDX21 by SPR\/BLI (kinetic profiling in vitro).\u003c\/li\u003e\n\u003cli\u003eGenerate antibodies to DDX21 and benchmark specificity in ELISA\/WB (control samples).\u003c\/li\u003e\n\u003c\/ul\u003e\u003cp\u003eInterpret results in the context of the biological system, assay format, and any known domain\/isoform constraints for the target.\u003c\/p\u003e\u003ch2\u003eNotes for experimental interpretation\u003c\/h2\u003e\u003cul\u003e\n\u003cli\u003eConsider species- and isoform-specific differences when comparing results across models or homologs.\u003c\/li\u003e\n\u003cli\u003eFor quantitative assays, include appropriate negative controls and matrix-matched spike-in concepts to assess non-specific signal.\u003c\/li\u003e\n\u003c\/ul\u003e\u003c!-- Sources (internal): - UniProtKB entry (Q9NR30) — UniProt: https:\/\/www.uniprot.org\/uniprotkb\/Q9NR30 - NCBI Gene search (DDX21) — NCBI: https:\/\/www.ncbi.nlm.nih.gov\/gene\/?term=DDX21 - PubMed search — NLM: https:\/\/pubmed.ncbi.nlm.nih.gov\/?term=DDX21 - Reactome pathway browser — Reactome: https:\/\/reactome.org\/ - InterPro protein family resource — EMBL-EBI: https:\/\/www.ebi.ac.uk\/interpro\/ --\u003e","brand":"CUSABIO TECHNOLOGY LLC","offers":[{"title":"1 mg","offer_id":53059274703213,"sku":"CSB-EP882081HU-1MG","price":1812.0,"currency_code":"USD","in_stock":true},{"title":"100 ug","offer_id":53059396796781,"sku":"CSB-EP882081HU-100UG","price":419.0,"currency_code":"USD","in_stock":true},{"title":"20 ug","offer_id":53059396829549,"sku":"CSB-EP882081HU-20UG","price":224.0,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0949\/7424\/7277\/files\/CSB-EP882081HU-SDS.jpg?v=1772280204","url":"https:\/\/www.ebiohippo.com\/products\/recombinant-human-nucleolar-rna-helicase-2-ddx21-bhp10514982","provider":"BioHippo","version":"1.0","type":"link"}