|
|
GEO help: Mouse over screen elements for information. |
|
Status |
Public on Feb 01, 2018 |
Title |
Surveillance of rRNA synthesis by an RNA helicase mediates tissue-specific developmental disorders |
Organism |
Homo sapiens |
Experiment type |
Genome binding/occupancy profiling by high throughput sequencing Expression profiling by high throughput sequencing
|
Summary |
Myriad of craniofacial disorders are caused by heterozygous mutations in general regulators of housekeeping cellular functions such as ribosome biogenesis. While it is understood that many of these highly tissue-specific malformations are a consequence of defects in cranial neural crest cells (cNCCs), an embryonic cell group that gives rise to most of the facial structures during embryogenesis, the mechanism underlying cell type-selectivity of these effects remains largely unknown. Here we show that DDX21, a DEAD-box RNA helicase involved in control of both RNA polymerase (Pol) I and Pol II dependent transcriptional arms of ribosome biogenesis, is a key mediator of the nucleolar stress response. Using an in vitro model of Treacher Collins Syndrome (TCS), a craniofacial disorder caused by heterozygous mutations in components of the Pol I transcriptional machinery, we demonstrate that perturbations in ribosomal RNA (rRNA) transcription induce DDX21-mediated surveillance mechanism in cNCCs, leading to DDX21 relocalization from the nucleolus to the nucleoplasm, its eviction from Pol I and Pol II chromatin targets and inhibition of rRNA processing. Importantly, these effects are cell type-selective, cell-autonomous and involve activation of the p53 pathway. We further show that cNCCs are characterized by the inherently high reservoir of p53 mRNA and sensitivity to p53-mediated apoptosis. Remarkably, preventing the loss of DDX21 from nucleolus and chromatin can rescue both the sensitivity to apoptosis and TCS-associated craniofacial phenotypes in vivo. This mechanism is not restricted to TCS, as gene function perturbations linked to other ribosomopathies with craniofacial manifestations also lead to the activation of DDX21 surveillance. Lastly, we provide evidence that inhibition of rRNA synthesis leads to rDNA damage, and furthermore, that rDNA damage is sufficient to activate DDX21 surveillance and elicits tissue-selective and dosage-dependent effects on craniofacial development in vivo.
|
|
|
Overall design |
Examination of DDX21 and TCOF1 binding to chromatin
Examination of DDX21 irCLIP from HeLa with DMSO or ActD treatments
|
|
|
Contributor(s) |
Calo E, Wysocka J |
Citation(s) |
29364875 |
|
Submission date |
Nov 02, 2016 |
Last update date |
Jul 25, 2021 |
Contact name |
Eliezer Calo |
E-mail(s) |
[email protected]
|
Organization name |
Massachusetts Institute of Technology
|
Department |
Biology
|
Lab |
calo
|
Street address |
31 Ames St, 68-270A
|
City |
Cambridge |
State/province |
MASSACHUSETTS |
ZIP/Postal code |
02139 |
Country |
USA |
|
|
Platforms (2) |
GPL16791 |
Illumina HiSeq 2500 (Homo sapiens) |
GPL18573 |
Illumina NextSeq 500 (Homo sapiens) |
|
Samples (10)
|
|
Relations |
BioProject |
PRJNA352129 |
SRA |
SRP092428 |
Supplementary file |
Size |
Download |
File type/resource |
GSE89420_HS_HeLa_irCLIP_DDX21_ActD_minus.bw |
1.3 Mb |
(ftp)(http) |
BW |
GSE89420_HS_HeLa_irCLIP_DDX21_ActD_plus.bw |
1.4 Mb |
(ftp)(http) |
BW |
GSE89420_HS_HeLa_irCLIP_DDX21_DMSO_minus.bw |
1.2 Mb |
(ftp)(http) |
BW |
GSE89420_HS_HeLa_irCLIP_DDX21_DMSO_plus.bw |
1.3 Mb |
(ftp)(http) |
BW |
GSE89420_RAW.tar |
41.9 Mb |
(http)(custom) |
TAR (of WIG) |
SRA Run Selector |
Raw data are available in SRA |
Processed data provided as supplementary file |
|
|
|
|
|