SPT5 regulates RNA polymerase II stability via Cullin 3–ARMC5 recognition [ChIP-seq]
Ontology highlight
ABSTRACT:
PROVIDER: PRJNA1162054 | ENA |
REPOSITORIES: ENA
Similar Datasets
Project description:The stability of RNA polymerase II (Pol II) is tightly regulated during transcriptional elongation for proper control of gene expression. Our recent studies revealed that promoter-proximal Pol II is destabilized via the ubiquitin E3 ligase cullin 3 (CUL3) upon loss of transcription elongation factor SPT5. Here, we investigate how CUL3 recognizes chromatin-bound Pol II as a substrate. Using an unbiased proteomic screening approach, we identify armadillo repeat-containing 5 (ARMC5) as a CUL3 adaptor required for VCP/p97-dependent degradation of SPT5-depleted, chromatin-bound Pol II. Genome-wide analyses indicate that ARMC5 targets promoter-proximal Pol II in a BTB domain–dependent manner. Further biochemical analysis demonstrates that interaction between ARMC5 and Pol II requires the transcriptional cyclin-dependent kinase 9 (CDK9), supporting a phospho-dependent degradation model. We propose that defective, promoter-proximal Pol II that lacks SPT5 is rapidly eliminated from chromatin in a noncanonical early termination pathway that requires CDK9-dependent interaction with the CUL3-ARMC5 ubiquitin ligase complex.
2025-01-24 | GSE277372 | GEO
Project description:The stability of RNA polymerase II (Pol II) is tightly regulated during transcriptional elongation for proper control of gene expression. Our recent studies revealed that promoter-proximal Pol II is destabilized via the ubiquitin E3 ligase cullin 3 (CUL3) upon loss of transcription elongation factor SPT5. Here, we investigate how CUL3 recognizes chromatin-bound Pol II as a substrate. Using an unbiased proteomic screening approach, we identify armadillo repeat-containing 5 (ARMC5) as a CUL3 adaptor required for VCP/p97-dependent degradation of SPT5-depleted, chromatin-bound Pol II. Genome-wide analyses indicate that ARMC5 targets promoter-proximal Pol II in a BTB domain–dependent manner. Further biochemical analysis demonstrates that interaction between ARMC5 and Pol II requires the transcriptional cyclin-dependent kinase 9 (CDK9), supporting a phospho-dependent degradation model. We propose that defective, promoter-proximal Pol II that lacks SPT5 is rapidly eliminated from chromatin in a noncanonical early termination pathway that requires CDK9-dependent interaction with the CUL3-ARMC5 ubiquitin ligase complex.
2025-01-24 | GSE277370 | GEO
Project description:SPT5 regulates RNA polymerase II stability via Cullin 3–ARMC5 recognition [RNA-Seq]
| PRJNA1162056 | ENA
Project description:The regulation of gene expression by RNA polymerase II (Pol II) is a multistep process requiring the concerted action of diverse transcription factors. Very little is known about in vivo function of transcription factor SPT5 as its deletion results in loss of viability. To circumvent this issue and define in vivo mechanism of action for SPT5, we employed acute degradation of SPT5 and studied its consequence on transcription. We find that SPT5 loss triggers degradation of the core Pol II subunit RPB1, a process which we show to be evolutionarily conserved from yeast to human. This RPB1 degradation requires the E3 ubiquitin ligase Cullin 3, the unfoldase VCP/p97 and a novel form of CDK9 kinase complex. SPT5 specifically stabilizes Pol II at promoter proximal regions, permitting Pol II release from promoters to gene bodies. Our findings provide mechanistic insight into the in vivo function of SPT5 in stabilization of promoter-proximal Pol II prior to release into gene bodies for safeguarding accurate gene expression.
2021-08-31 | GSE168827 | GEO
Project description:ARMC5 is an armadillo domain (ARM)-containing protein. We found that Armc5 KO mice had an increased incidence of neural tube defects (NTDs). ARMC5 is the substrate recognition component of a ubiquitin ligase that targets POLR2A, the largest subunit of RNA polymerase II (Pol II). Surprisingly, the absence of ARMC5 caused the accumulation of not only POLR2A, but most of the other 11 Pol II subunits associated with POLR2A, indicating that the degradation of the whole Pol II complex is compromised. This did not lead to generalized Pol II stalling or a generalized decrease in mRNA transcription. In neural progenitor cells, ARMC5 KO only dysregulated 106 genes, some of which are known to be involved in neural tube development. FOLH1, critical for folate metabolism and vital in neural tube development, was downregulated in the KO intestine, suggesting that it is a downstream effector gene for NTD. To assess whether ARMC5 gene mutation was associated with human NTD, we conducted whole-exome sequencing of 511 patients with myelomeningocele, a severe form of NTD. Nine deleterious single nucleotide variants were discovered in the ARMC5 coding sequence. Four of them were validated in that they weakened the interaction between ARMC5 and POLR2A; consequently, POLR2A ubiquitination was decreased. This proves that our findings in mice are relevant to human NTD; it also supports the role of Pol II in mediating NTD pathogenesis. Our findings indicate that mutations in ARMC5 increase the risk of NTD and support the role of Pol II in NTD pathogenesis. Further investigation is needed to determine the cause-and-effect relationship between an enlarged Pol II pool and NTD and to validate the potential role of downregulated FOLH1 expression in NTD pathogenesis.
2023-12-06 | PXD047572 | Pride
Project description:ARMC5 is an armadillo domain (ARM)-containing protein. We found that Armc5 KO mice had an increased incidence of neural tube defects (NTDs). ARMC5 is the substrate recognition component of a ubiquitin ligase that targets POLR2A, the largest subunit of RNA polymerase II (Pol II). Surprisingly, the absence of ARMC5 caused the accumulation of not only POLR2A, but most of the other 11 Pol II subunits associated with POLR2A, indicating that the degradation of the whole Pol II complex is compromised. This did not lead to generalized Pol II stalling or a generalized decrease in mRNA transcription. In neural progenitor cells, ARMC5 KO only dysregulated 106 genes, some of which are known to be involved in neural tube development. FOLH1, critical for folate metabolism and vital in neural tube development, was downregulated in the KO intestine, suggesting that it is a downstream effector gene for NTD. To assess whether ARMC5 gene mutation was associated with human NTD, we conducted whole-exome sequencing of 511 patients with myelomeningocele, a severe form of NTD. Nine deleterious single nucleotide variants were discovered in the ARMC5 coding sequence. Four of them were validated in that they weakened the interaction between ARMC5 and POLR2A; consequently, POLR2A ubiquitination was decreased. This proves that our findings in mice are relevant to human NTD; it also supports the role of Pol II in mediating NTD pathogenesis. Our findings indicate that mutations in ARMC5 increase the risk of NTD and support the role of Pol II in NTD pathogenesis. Further investigation is needed to determine the cause-and-effect relationship between an enlarged Pol II pool and NTD and to validate the potential role of downregulated FOLH1 expression in NTD pathogenesis.
2023-12-06 | PXD047533 | Pride
Project description:Activation induced cytidine deaminase (AID) initiates antibody gene diversification by creating U:G mismatches. However, AID is not specific for antibody genes. Off-target lesions can activate oncogenes or cause chromosome translocations. Despite its importance in these key transactions little is known about how AID finds its target sites. To examine AID regulation we performed an shRNA screen. We found that Spt5, a factor associated with paused RNA polymerase II (Pol II) and single stranded DNA (ssDNA), is required for class switch recombination (CSR). Spt5 interacts with AID, it is required for the association of AID and Pol II, and for AID recruitment to switch regions. ChIP-seq experiments reveal that Spt5 co-localizes with AID and stalled Pol II. Further, Spt5 accumulation at sites of Pol II pausing is predictive of AID-induced mutation. Our data suggest that Spt5 acts as an adaptor, which brings AID to Pol II on target DNA. PolII, AID, and Spt5 were immunoprecipitated from in vitro activated B cells. For Spt5 and AID, two different antibodies were used in separate, biological replicates
2010-10-05 | E-GEOD-24178 | biostudies-arrayexpress
Project description:The timely termination of RNA polymerase II (Pol II) transcription is essential for recycling of this enzyme and preventing transcriptional interference. While 5'-3' exonuclease Xrn2 is known to degrade nascent RNA after poly(A) site cleavage to promote Pol II release, its molecular mechanism remains not fully understood. Spt5 is one of highly conserved transcription factors that controls and regulates multiple aspects of Pol II transcription. Here, using mass spectrometry analysis of immunoprecipitated Flag-tagged Spt5-WT and Spt5-mutant complexes from fission yeast cells, we show that Xrn2 is highly enriched in these samples. Through in vitro BS3 crosslinking experiments with purified components, we further demonstrated that Xrn2 associates with transcription machinery and we probed interfaces between different subunits of transcription machinery
2024-11-22 | PXD058168 | Pride
Project description:The MYC oncoprotein binds to promoter-proximal regions of virtually all transcribed genes and is expressed in a strictly growth factor-dependent manner in non-tumor cells. Here we show that MYC directly binds SPT5, a subunit of the RNA polymerase II (POL2) elongation factor DSIF. MYC recruits SPT5 to genes and enables the CDK7-dependent transfer of SPT5 onto POL2. Consistent with known functions of SPT5, MYC is required for fast and processive transcription elongation. In addition, MYC increases the directionality of promoters by stimulating sense transcription and suppressing the synthesis of antisense RNAs. Our results argue that MYC controls the productive assembly of POL2 with general elongation factors to form processive elongation complexes. The high levels of MYC that are expressed in tumors sequester SPT5 into non-functional complexes, slows transcription at growth-suppressive genes and promotes uncontrolled cellular growth.
2019-03-27 | GSE115365 | GEO
Project description:RNA polymerase II (Pol II) termination is a crucial step in the transcriptional cycle, ensuring the recycling of Pol II and preventing interference with neighbouring gene transcription. Xrn2 is an enzyme with 5'-3'- exonuclease activity, responsible for degrading RNA that is still being transcribed by Pol II after cleavage at the poly(A) site, ultimately leading to Pol II termination. We have confirmed that Xrn2's catalytic activity is essential for timely transcription termination. Furthermore, we have discovered a link between Xrn2 and the conserved, multifunctional transcription factor Spt5. Importantly, our research demonstrates that Xrn2 interacts with Pol II/Spt5 complexes. Additionally, when Spt5 is depleted, it not only impairs global transcription but also results in defective transcription termination. On the other hand, absence of Spt5 leads to the derepression of non-coding transcription and premature termination/attenuation at the 5'-end of coding genes. We propose that Spt5 acts as a "licensing" factor, ensuring that Pol II complexes are properly assembled for efficient transcription and co-transcriptional pre-mRNA processing.
2024-09-30 | GSE273510 | GEO