| 1997 |
CA150 (TCERG1) is a nuclear protein associated with the RNA polymerase II holoenzyme; immunodepletion of CA150 abolished Tat trans-activation in vitro, and both CA150 and Tat were shown to co-immunoprecipitate with the RNAPII holoenzyme, establishing CA150 as a component required for Tat-dependent HIV-1 transcriptional activation. |
Biochemical purification, molecular cloning, immunodepletion from in vitro transcription assay, immunoprecipitation |
Molecular and cellular biology |
High |
9315662
|
| 1999 |
CA150 regulates RNA polymerase II elongation in a TATA-box-dependent manner at the HIV-1 LTR promoter; functional assays showed CA150 affects transcription elongation complex processivity and requires the same cis-elements as Tat activation. |
In vivo reporter gene functional assays, transcription elongation analysis |
Molecular and cellular biology |
Medium |
10373521
|
| 2000 |
The FF domains of CA150 (TCERG1) directly bind the hyperphosphorylated C-terminal repeat domain (phosphoCTD) of RNA polymerase II; the fifth FF domain alone was sufficient for phosphoCTD binding, identifying FF domains as protein-interaction modules that bind the phosphoCTD. |
Phospho-CTD affinity purification, binding assays with recombinant FF domain fragments |
Proceedings of the National Academy of Sciences of the United States of America |
High |
10908677
|
| 2001 |
CA150 represses RNAPII transcription elongation; its FF repeat domains bind directly to the phosphorylated CTD of RNAPII (required for repression), while WW1 and WW2 domains interact directly with the splicing-transcription factor SF1 through a novel proline-rich motif in the C-terminal half of SF1, and these interactions are required for efficient CA150-mediated transcriptional repression. |
In vitro binding assays, domain deletion/mutation analysis, co-immunoprecipitation, reporter transcription assays |
Molecular and cellular biology |
High |
11604498
|
| 2001 |
CA150 (TCERG1) interacts in vitro with full-length huntingtin (htt) from lymphoblastoid cells and co-localizes partially with ubiquitin-positive aggregates in HD brain tissue; a C. elegans WW-domain protein (ZK1127.9) was identified as an htt-interacting protein via yeast two-hybrid, with CA150 as its human homologue. |
Yeast two-hybrid screen, in vitro binding assay with cell lysates, immunohistochemistry |
Proceedings of the National Academy of Sciences of the United States of America |
Medium |
11172033
|
| 2004 |
CA150/TCERG1 FF domains interact with multiple nuclear binding partners including Tat-SF1; individual FF domains bind Tat-SF1 peptide ligands noncooperatively with affinities of 150–500 µM through consensus acidic motifs (D/E)2/5-F/W/Y-(D/E)2/5; phosphorylation at both Ser2 and Ser5 of the RNAPII CTD generates the required negative charges for FF domain recognition. |
Mass spectrometry identification of binding partners, NMR titration, peptide binding assays |
Molecular and cellular biology |
High |
15485897
|
| 2006 |
CA150/TCERG1 localizes to nuclear speckles enriched in splicing factors; this localization requires FF domains (not WW domains) and is not affected by inhibition of transcription or RNAPII CTD phosphorylation; both the N-terminal WW-domain region and a C-terminal FF-domain region are required to assemble transcription and splicing components into higher-order complexes. |
Immunofluorescence/confocal microscopy, domain deletion mutant analysis, biochemical co-purification assays |
Molecular and cellular biology |
High |
16782886
|
| 2006 |
CA150 expression rescues striatal cell death induced by mutant huntingtin in both lentiviral overexpression (rat) and knock-in (mouse cell) models; rescue requires the (Gln-Ala)38 repeat, which is necessary for nuclear restriction of exogenous CA150 but dispensable for CA150 transcriptional repression activity, suggesting nuclear localization is critical for neuroprotection. |
Lentiviral overexpression in rat striatum, knock-in mouse cell system, cell death assays, confocal microscopy, mutant rescue experiments |
The Journal of neuroscience |
Medium |
16641246
|
| 2008 |
Knockdown of TCERG1 by siRNA leads to widespread alterations in alternative mRNA processing and affects 3'-UTR processing; TCERG1 cellular targets are enriched in microRNA-binding sites, supporting a role for TCERG1 in coupling transcription and mRNA processing. |
siRNA knockdown, microarray gene expression analysis, RT-PCR validation, computational alternative processing analysis |
The Journal of biological chemistry |
Medium |
18187414
|
| 2009 |
Crystal structure of the first three tandem FF domains of CA150/TCERG1 at 2.7 Å resolution reveals that consecutive FF domains are connected by a continuous alpha-helix (the last helix of one FF domain merges into the first helix of the next), creating an elongated arrangement that exposes charged residues for intermolecular interactions. |
X-ray crystallography (2.7 Å resolution), peptide binding studies |
Journal of molecular biology |
High |
19660470
|
| 2009 |
NMR solution structure and relaxation analysis of the CA150 FF1+FF2 tandem shows that the interdomain linker forms a helical extension of helix α3 of FF1, maintaining distance between the two FF domains without fixing their relative orientation; the domains adopt a dumbbell-like arrangement allowing individual FF domains to maneuver for recognition of flexible partners such as the intrinsically-disordered phosphoCTD. |
NMR spectroscopy (solution structure + relaxation experiments) |
Journal of molecular biology |
High |
19715701
|
| 2010 |
TCERG1 is sumoylated at Lys-503 and Lys-608 by SUMO family proteins; TCERG1 binds the E2 SUMO-conjugating enzyme Ubc9; mutation of the SUMO acceptor lysines enhanced TCERG1 transcriptional activity (but did not affect nuclear speckle localization or alternative splicing function), establishing that sumoylation negatively regulates TCERG1 transcriptional elongation activity. |
Sumoylation assays, site-directed mutagenesis of SUMO acceptor lysines, interaction assays with Ubc9, reporter transcription assays, immunofluorescence |
The Journal of biological chemistry |
High |
20215116
|
| 2010 |
TCERG1 inhibits the transcriptional and anti-proliferative activities of C/EBPα; the inhibitory activity maps to the amino-terminal region of TCERG1; co-expression with C/EBPα causes redistribution of TCERG1 from nuclear speckles to pericentromeric sites where C/EBPα resides, and this nuclear relocalization is required for the inhibitory activity. |
Reporter gene assays, confocal microscopy with nuclear localization mutants, co-expression experiments |
Journal of cellular biochemistry |
Medium |
19911371
|
| 2011 |
TCERG1 regulates alternative splicing of the apoptosis gene Bcl-x in a promoter-dependent manner: it promotes the short pro-apoptotic Bcl-x(S) isoform through the SB1 regulatory element in exon 2; TCERG1 associates with the Bcl-x pre-mRNA; it modifies the elongation rate of RNAPII on endogenous Bcl-x and affects pre-mRNA levels at distal regions, indicating a kinetic coupling mechanism linking RNAPII pausing to splice-site selection. |
siRNA knockdown, RT-PCR splicing assays, chromatin immunoprecipitation (RNA association), RNAPII transcription rate analysis, slow polymerase mutant rescue experiments |
Molecular and cellular biology |
High |
22158966
|
| 2011 |
TCERG1 redistribution from nuclear speckles to pericentromeric regions upon C/EBPα co-expression does not require C/EBPα to be transcriptionally active or to be localized to pericentromeric heterochromatin itself; TCERG1 can inhibit C/EBPα activity regardless of its nuclear location, indicating the inhibitory mechanism is not simply sequestration at heterochromatin. |
Confocal microscopy with C/EBPα mutants (V296A and others), reporter assays |
Journal of cellular biochemistry |
Medium |
21503969
|
| 2012 |
The FF4 and FF5 domains of TCERG1 constitute a speckle-periphery targeting signal; this FF4-FF5 pair folds as a functional unit in solution and is both necessary and sufficient (when fused to heterologous proteins) to direct proteins to the periphery of nuclear speckles; this targeting signal also contributes to alternative splicing regulation of a reporter pre-mRNA. |
Domain deletion/fusion constructs, confocal immunofluorescence, NMR folding assay, in vivo splicing reporter assay |
The Journal of biological chemistry |
High |
22453921
|
| 2013 |
Structural characterization (NMR + biochemistry) of the tandem FF4-FF5-FF6 domains of TCERG1 shows a rigid integral domain structure; binding to the phosphoCTD of RNAPII requires simultaneous phosphorylation at Ser2, Ser5, AND Ser7 within two consecutive heptad repeats, and is mediated by CTD-docking sites on FF4 and FF5 (but not FF6) — the first example of a nuclear factor requiring all three phospho-Ser marks for high-affinity CTD binding. |
NMR structure determination, peptide column binding assays, NMR titrations, site-specific phospho-CTD peptides |
The Journal of biological chemistry |
High |
23436654
|
| 2013 |
TCERG1 depletion reduces basal and Tat-activated transcription from the HIV-1 LTR; TCERG1 directly affects RNAPII elongation rate in vivo at the HIV-1 locus and increases phosphorylation of Ser2 within the RNAPII CTD, suggesting a mechanism by which TCERG1 relieves transcriptional pausing by promoting CTD Ser2 phosphorylation. |
siRNA knockdown, ChIP for RNAPII distribution, nascent RNA quantification at distal regions, Ser2 phospho-CTD analysis |
Retrovirology |
Medium |
24165037
|
| 2015 |
TCERG1 modulates alternative splicing of both Bcl-x and Fas/CD95 genes; changes in Bcl-x splicing by TCERG1 correlate with induction of apoptosis (assessed by annexin-V binding, caspase-3 cleavage, PARP-1 cleavage, mitochondrial membrane permeabilization); depletion of TCERG1 reduces activated Bak levels, linking TCERG1-mediated splicing to the mitochondrial apoptosis pathway. |
siRNA knockdown and overexpression, RT-PCR splicing assays, cell death assays (annexin-V, caspase cleavage, PARP cleavage), mitochondrial membrane potential assay, Bak activation assay |
PloS one |
Medium |
26462236
|
| 2016 |
Live-cell FRAP experiments show TCERG1 is highly mobile in the nucleoplasm; DRB (transcription elongation inhibitor) but not α-amanitin (RNAPII degrader) reduces TCERG1 mobility, indicating interaction with paused elongation complexes; TCERG1 is recruited to active transcription sites independently of RNAPII CTD phosphorylation; mobility is further reduced when splicing occurs co-transcriptionally, indicating formation of new macromolecular complexes during co-transcriptional splicing, consistent with TCERG1 coupling elongation and splicing via transient rather than stable interactions. |
Live-cell FRAP (fluorescence recovery after photobleaching), DRB and α-amanitin treatment, spliceostatin A treatment, cotranscriptional splicing reporter |
RNA |
High |
26873599
|
| 2016 |
The glutamine-alanine (QA) repeat domain of TCERG1 is required for inhibition of C/EBPα growth arrest activity; deletion of the QA repeat abrogates TCERG1–C/EBPα complex formation, prevents relocalization from nuclear speckles to pericentromeric regions, and enlarges nuclear speckles; a minimal number of QA repeats is required for inhibitory activity. |
QA-repeat deletion and truncation mutants, co-immunoprecipitation, confocal microscopy, growth arrest functional assays |
Journal of cellular biochemistry |
Medium |
26264132
|
| 2018 |
TCERG1 (human homolog of Drosophila CG42724) was identified as a genetic modulator of TDP-43 production; CG42724 overexpression in a Drosophila model promotes production of TDP-43 mRNA transcripts efficiently released into the cytoplasm; overexpression of human TCERG1 in mammalian cells increases TDP-43 protein steady-state levels. |
Drosophila genetic screen, mRNA transcript analysis, mammalian cell overexpression with protein level quantification |
Acta neuropathologica communications |
Medium |
30541625
|