Overview
| Uniprot ID | Q3B8Q1 |
|---|
| Protein Name | Nucleolar RNA helicase 2 |
|---|
| Gene Name | Ddx21 |
|---|
| Organism | Rattus norvegicus |
|---|
Kla Sites from experimental identification
| Position |
Flanking peptide |
| 39 |
RKEKPKSKTDEATEG |
| 54 |
VEEAASSKVKAVKKK |
| 78 |
PKSKKAKKQEEEPQD |
Function
RNA 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 a 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 (By similarity). 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 (By similarity)
Protein Sequence
10
MPGKLRSASK
20
SESEGTEESM
30
ETLQKPSEKK
40
TRKEKPKSKT
50
DEATEGVEEA
60
ASSKVKAVKK
70
KGPSEDDVGP
80
PKSKKAKKQE
90
EEPQDDPASK
100
SKTSKKKKEP
110
LEKKAPSAKT
120
KEMKAEEPSE
130
EEADAPKPKK
140
TKKGKEANGD
150
VGEKSPGLKN
160
GLSHPKPDSS
170
STQAPGEESE
180
TEKEIPVEQK
190
EGAFSNFPIS
200
EETVKLLKAR
210
GVNFLFPIQA
220
KTFHHVYSGK
230
DLIAQARTGT
240
GKTFSFAIPL
250
IEKLQGGLQE
260
RKRGRAPQVL
270
VLAPTRELAN
280
QVSKDFSDIT
290
KKLSVACFYG
300
GTPYGGQIER
310
MRSGIDILVG
320
TPGRIKDHLQ
330
NGKLDLTKLK
340
HVVLDEVDQM
350
LDMGFADQVE
360
EILCVAYKKD
370
SEDNPQTLLF
380
SATCPHWVFN
390
VAKKYMKSTY
400
EQVDLIGKKT
410
QKAAITVEHL
420
AIKCHWTERA
430
AVIGDVIRVY
440
SGHQGRTIIF
450
CETKKDAQEL
460
SQNTCIKQDA
470
QSLHGDIPQK
480
QREITLKGFR
490
NGNFGVLVAT
500
NVAARGLDIP
510
EVDLVVQSCP
520
PKDVESYIHR
530
SGRTGRAGRT
540
GVCICFYQHK
550
EEYQLAQVEQ
560
KAGIKFKRIG
570
VPSATEIIKA
580
SSKDAIRLLD
590
SVPPTAIGHF
600
KQSAEKLIEE
610
KGAVEALAAA
620
LAHISGATSV
630
DQRSLINSQA
640
GFVTMILRCS
650
VEMPNISYAW
660
KELKEQLGES
670
IDAKVKGMVF
680
LKGKLGVCFD
690
VRTEAVTEIK
700
EKWHDSRRWQ
710
LTVATEQPEL
720
EGPPEGYRGG
730
RGQRDGSRGS
740
FRGQRGGSRN
750
FRGQGQRGGS
760
RNFRGQRPGG
770
GNKSNRSPNK
780
GQKRSFSKAF
GQ
Gene Ontology
| Classification |
GO ID |
Description |
| Cellular Component |
GO:0110016 |
B-WICH complex |
| Cellular Component |
GO:0005694 |
chromosome |
| Cellular Component |
GO:0005829 |
cytosol |
| Cellular Component |
GO:0005739 |
mitochondrion |
| Cellular Component |
GO:0005730 |
nucleolus |
| Cellular Component |
GO:0005654 |
nucleoplasm |
| Molecular Function |
GO:0097322 |
7SK snRNA binding |
| Molecular Function |
GO:0005524 |
ATP binding |
| Molecular Function |
GO:0016887 |
ATP hydrolysis activity |
| Molecular Function |
GO:0003725 |
double-stranded RNA binding |
| Molecular Function |
GO:0042802 |
identical protein binding |
| Molecular Function |
GO:0035198 |
miRNA binding |
| Molecular Function |
GO:0003729 |
mRNA binding |
| Molecular Function |
GO:0003724 |
RNA helicase activity |
| Molecular Function |
GO:0019843 |
rRNA binding |
| Molecular Function |
GO:0030515 |
snoRNA binding |
| Biological Process |
GO:0051607 |
defense response to virus |
| Biological Process |
GO:0045087 |
innate immune response |
| Biological Process |
GO:0043123 |
positive regulation of canonical NF-kappaB signal transduction |
| Biological Process |
GO:0002735 |
positive regulation of myeloid dendritic cell cytokine production |
| Biological Process |
GO:0045945 |
positive regulation of transcription by RNA polymerase III |
| Biological Process |
GO:0062176 |
R-loop processing |
| Biological Process |
GO:0043330 |
response to exogenous dsRNA |
| Biological Process |
GO:0009615 |
response to virus |
| Biological Process |
GO:0006364 |
rRNA processing |
| Biological Process |
GO:0006366 |
transcription by RNA polymerase II |
Reference
[1] Sheng L, Xu H, Wang Y, Ni J, Xiang T et al.. Systematic analysis of lysine lactylation in nucleus pulposus cells.. iScience 27(11):111157. 2024 Nov 15. PMID: 39524337.