keyword
MENU ▼
Read by QxMD icon Read
search

P-tefb

keyword
https://www.readbyqxmd.com/read/28431135/reconstitution-of-a-functional-7sk-snrnp
#1
John E Brogie, David H Price
The 7SK small nuclear ribonucleoprotein (snRNP) plays a central role in RNA polymerase II elongation control by regulating the availability of active P-TEFb. We optimized conditions for analyzing 7SK RNA by SHAPE and demonstrated a hysteretic effect of magnesium on 7SK folding dynamics including a 7SK GAUC motif switch. We also found evidence that the 5΄ end pairs alternatively with two different regions of 7SK giving rise to open and closed forms that dictate the state of the 7SK motif. We then used recombinant P-TEFb, HEXIM1, LARP7 and MEPCE to reconstruct a functional 7SK snRNP in vitro...
April 20, 2017: Nucleic Acids Research
https://www.readbyqxmd.com/read/28426094/sirt7-dependent-deacetylation-of-cdk9-activates-rna-polymerase-ii-transcription
#2
Maximilian F Blank, Sifan Chen, Fabian Poetz, Martina Schnölzer, Renate Voit, Ingrid Grummt
SIRT7 is an NAD+-dependent protein deacetylase that regulates cell growth and proliferation. Previous studies have shown that SIRT7 is required for RNA polymerase I (Pol I) transcription and pre-rRNA processing. Here, we took a proteomic approach to identify novel molecular targets and characterize the role of SIRT7 in non-nucleolar processes. We show that SIRT7 interacts with numerous proteins involved in transcriptional regulation and RNA metabolism, the majority of interactions requiring ongoing transcription...
March 17, 2017: Nucleic Acids Research
https://www.readbyqxmd.com/read/28422315/regulation-of-the-alternative-splicing-and-function-of-cyclin-t1-by-the-serine-arginine-rich-protein-asf-sf2
#3
Jieqiong Zhou, Guozhen Gao, Panpan Hou, Chun-Mei Li, Deyin Guo
Positive transcription elongation factor-b (P-TEFb) is required for the release of RNA polymerase II (RNAPII) from its pause near the gene promoters and thus for efficient proceeding to the transcription elongation. It consists of two core subunits - CDK9 and one of T-typed or K-typed cyclin, of which, cyclin T1/CDK9 is the major and most studied combination. We have previously identified a novel splice variant of cyclin T1, cyclin T1b, which negatively regulates the transcription elongation of HIV-1 genes as well as several host genes...
April 19, 2017: Journal of Cellular Biochemistry
https://www.readbyqxmd.com/read/28407486/transcriptional-elongation-of-hsv-immediate-early-genes-by-the-super-elongation-complex-drives-lytic-infection-and-reactivation-from-latency
#4
Roberto Alfonso-Dunn, Anne-Marie W Turner, Pierre M Jean Beltran, Jesse H Arbuckle, Hanna G Budayeva, Ileana M Cristea, Thomas M Kristie
The cellular transcriptional coactivator HCF-1 is required for initiation of herpes simplex virus (HSV) lytic infection and for reactivation from latency in sensory neurons. HCF-1 stabilizes the viral Immediate Early (IE) gene enhancer complex and mediates chromatin transitions to promote IE transcription initiation. In infected cells, HCF-1 was also found to be associated with a network of transcription elongation components including the super elongation complex (SEC). IE genes exhibit characteristics of genes controlled by transcriptional elongation, and the SEC-P-TEFb complex is specifically required to drive the levels of productive IE mRNAs...
April 12, 2017: Cell Host & Microbe
https://www.readbyqxmd.com/read/28394257/cooperative-gene-activation-by-af4-and-dot1l-drives-mll-rearranged-leukemia
#5
Hiroshi Okuda, Boban Stanojevic, Akinori Kanai, Takeshi Kawamura, Satoshi Takahashi, Hirotaka Matsui, Akifumi Takaori-Kondo, Akihiko Yokoyama
The eleven-nineteen leukemia (ENL) protein family, composed of ENL and AF9, is a common component of 3 transcriptional modulators: AF4-ENL-P-TEFb complex (AEP), DOT1L-AF10-ENL complex (referred to as the DOT1L complex) and polycomb-repressive complex 1 (PRC1). Each complex associates with chromatin via distinct mechanisms, conferring different transcriptional properties including activation, maintenance, and repression. The mixed-lineage leukemia (MLL) gene often fuses with ENL and AF10 family genes in leukemia...
April 10, 2017: Journal of Clinical Investigation
https://www.readbyqxmd.com/read/28351991/the-composition-of-the-arabidopsis-rna-polymerase-ii-transcript-elongation-complex-reveals-the-interplay-between-elongation-and-mrna-processing-factors
#6
Wojciech Antosz, Alexander Pfab, Hans F Ehrnsberger, Philipp Holzinger, Karin Köllen, Simon A Mortensen, Astrid Bruckmann, Thomas Schubert, Gernot Längst, Joachim Griesenbeck, Veit Schubert, Marion Grasser, Klaus D Grasser
Transcript elongation factors (TEFs) are a heterogeneous group of proteins that control the efficiency of transcript elongation of subsets of genes by RNA polymerase II (RNAPII) in the chromatin context. Using reciprocal tagging in combination with affinity-purification and mass spectrometry, we demonstrate that in Arabidopsis thaliana, the TEFs SPT4/SPT5, SPT6, FACT, PAF1-C, and TFIIS co-purified with each other and with elongating RNAPII, while P-TEFb was not among the interactors. Additionally, NAP1 histone chaperones, ATP-dependent chromatin remodelling factors, and some histone-modifying enzymes including Elongator were repeatedly found associated with TEFs...
March 28, 2017: Plant Cell
https://www.readbyqxmd.com/read/28345603/pja2-ubiquitinates-the-hiv-1-tat-protein-with-atypical-chain-linkages-to-activate-viral-transcription
#7
Tyler B Faust, Yang Li, Gwendolyn M Jang, Jeffrey R Johnson, Shumin Yang, Amit Weiss, Nevan J Krogan, Alan D Frankel
Transcription complexes that assemble at the HIV-1 promoter efficiently initiate transcription but generate paused RNA polymerase II downstream from the start site. The virally encoded Tat protein hijacks positive transcription elongation factor b (P-TEFb) to phosphorylate and activate this paused polymerase. In addition, Tat undergoes a series of reversible post-translational modifications that regulate distinct steps of the transcription cycle. To identify additional functionally important Tat cofactors, we performed RNAi knockdowns of sixteen previously identified Tat interactors and found that a novel E3 ligase, PJA2, ubiquitinates Tat in a non-degradative manner and specifically regulates the step of HIV transcription elongation...
March 27, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28340332/super-elongation-complex-promotes-early-hiv-transcription-and-its-function-is-modulated-by-p-tefb
#8
Alona Kuzmina, Simona Krasnopolsky, Ran Taube
Early work on the control of transcription of the human immunodeficiency virus (HIV) laid the foundation for our current knowledge of how RNA Polymerase II is released from promoter-proximal pausing sites and transcription elongation is enhanced. The viral Tat activator recruits Positive Transcription Elongation Factor b (P-TEFb) and Super Elongation Complex (SEC) that jointly drive transcription elongation. While substantial progress in understanding the role of SEC in HIV gene transcription elongation has been obtained, defining of the mechanisms that govern SEC functions is still limited, and the role of SEC in controlling HIV transcription in the absence of Tat is less clear...
February 17, 2017: Transcription
https://www.readbyqxmd.com/read/28322550/multiplex-substrate-profiling-by-mass-spectrometry-for-kinases-as-a-method-for-revealing-quantitative-substrate-motifs
#9
Nicole O Meyer, Anthony J O'Donoghue, Ursula Schulze-Gahmen, Matthew Ravalin, Steven M Moss, Michael B Winter, Giselle M Knudsen, Charles S Craik
The more than 500 protein kinases comprising the human kinome catalyze hundreds of thousands of phosphorylation events to regulate a diversity of cellular functions; however, the extended substrate specificity is still unknown for many of these kinases. We report here a method for quantitatively describing kinase substrate specificity using an unbiased peptide library-based approach with direct measurement of phosphorylation by tandem liquid chromatography-tandem mass spectrometry (LC-MS/MS) peptide sequencing (multiplex substrate profiling by mass spectrometry, MSP-MS)...
April 4, 2017: Analytical Chemistry
https://www.readbyqxmd.com/read/28265070/bet-n-terminal-bromodomain-inhibition-selectively-blocks-th17-cell-differentiation-and-ameliorates-colitis-in-mice
#10
Kalung Cheung, Geming Lu, Rajal Sharma, Adam Vincek, Ruihua Zhang, Alexander N Plotnikov, Fan Zhang, Qiang Zhang, Ying Ju, Yuan Hu, Li Zhao, Xinye Han, Jamel Meslamani, Feihong Xu, Anbalagan Jaganathan, Tong Shen, Hongfa Zhu, Elena Rusinova, Lei Zeng, Jiachi Zhou, Jianjun Yang, Liang Peng, Michael Ohlmeyer, Martin J Walsh, David Y Zhang, Huabao Xiong, Ming-Ming Zhou
T-helper 17 (Th17) cells have important functions in adaptor immunity and have also been implicated in inflammatory disorders. The bromodomain and extraterminal domain (BET) family proteins regulate gene transcription during lineage-specific differentiation of naïve CD4(+) T cells to produce mature T-helper cells. Inhibition of acetyl-lysine binding of the BET proteins by pan-BET bromodomain (BrD) inhibitors, such as JQ1, broadly affects differentiation of Th17, Th1, and Th2 cells that have distinct immune functions, thus limiting their therapeutic potential...
March 14, 2017: Proceedings of the National Academy of Sciences of the United States of America
https://www.readbyqxmd.com/read/28254838/the-7sk-snrnp-associates-with-the-little-elongation-complex-to-promote-snrna-gene-expression
#11
Sylvain Egloff, Patrice Vitali, Michael Tellier, Raoul Raffel, Shona Murphy, Tamás Kiss
The 7SK small nuclear RNP (snRNP), composed of the 7SK small nuclear RNA (snRNA), MePCE, and Larp7, regulates the mRNA elongation capacity of RNA polymerase II (RNAPII) through controlling the nuclear activity of positive transcription elongation factor b (P-TEFb). Here, we demonstrate that the human 7SK snRNP also functions as a canonical transcription factor that, in collaboration with the little elongation complex (LEC) comprising ELL, Ice1, Ice2, and ZC3H8, promotes transcription of RNAPII-specific spliceosomal snRNA and small nucleolar RNA (snoRNA) genes...
April 3, 2017: EMBO Journal
https://www.readbyqxmd.com/read/28215221/targeting-chromatin-remodeling-in-inflammation-and-fibrosis
#12
J Yang, B Tian, A R Brasier
Mucosal surfaces of the human body are lined by a contiguous epithelial cell surface that forms a barrier to aerosolized pathogens. Specialized pattern recognition receptors detect the presence of viral pathogens and initiate protective host responses by triggering activation of the nuclear factor κB (NFκB)/RelA transcription factor and formation of a complex with the positive transcription elongation factor (P-TEFb)/cyclin-dependent kinase (CDK)9 and Bromodomain-containing protein 4 (BRD4) epigenetic reader...
2017: Advances in Protein Chemistry and Structural Biology
https://www.readbyqxmd.com/read/28199965/whole-exome-sequencing-identified-a-homozygous-brdt-mutation-in-a-patient-with-acephalic-spermatozoa
#13
Lin Li, Yanwei Sha, Xi Wang, Ping Li, Jing Wang, Kehkooi Kee, Binbin Wang
Acephalic spermatozoa is a very rare disorder of male infertility. Here, in a patient from from a consanguineous family, we have identified, by whole-exome sequencing, a homozygous mutation (c.G2783A, p.G928D) in the BRDT gene. The gene product, BRDT, is a testis-specific protein that is considered an important drug target for male contraception. The G928D mutation is in the P-TEFb binding domain, which mediates the interaction with transcription elongation factor and might affect the transcriptional activities of downstream genes...
March 21, 2017: Oncotarget
https://www.readbyqxmd.com/read/28188267/phosphorylation-of-spt5-by-cdkd-2-is-required-for-vip5-recruitment-and-normal-flowering-in-arabidopsis-thaliana
#14
Chengyuan Lu, Yongke Tian, Shiliang Wang, Yanhua Su, Ting Mao, Tongtong Huang, Qingqing Chen, Zuntao Xu, Yong Ding
The elongation factor suppressor of Ty 5 homolog (Spt5) is a regulator of transcription and histone methylation. In humans, phosphorylation of SPT5 by P-TEFb, a protein kinase composed of Cyclin-dependent kinase 9 (CDK9) and cyclin T, interacts with the RNA polymerase II-associated factor1 (PAF1) complex. However, the mechanism of SPT5 phosphorylation is not well understood in plants. Here, we examine the function of SPT5 in Arabidopsis thaliana and find that spt5 mutant flowers early under long-day and short-day conditions...
February 2017: Plant Cell
https://www.readbyqxmd.com/read/28178316/md-simulation-of-the-tat-cyclin-t1-cdk9-complex-revealing-the-hidden-catalytic-cavity-within-the-cdk9-molecule-upon-tat-binding
#15
Kaori Asamitsu, Takatsugu Hirokawa, Takashi Okamoto
In this study, we applied molecular dynamics (MD) simulation to analyze the dynamic behavior of the Tat/CycT1/CDK9 tri-molecular complex and revealed the structural changes of P-TEFb upon Tat binding. We found that Tat could deliberately change the local flexibility of CycT1. Although the structural coordinates of the H1 and H2 helices did not substantially change, H1', H2', and H3' exhibited significant changes en masse. Consequently, the CycT1 residues involved in Tat binding, namely Tat-recognition residues (TRRs), lost their flexibility with the addition of Tat to P-TEFb...
2017: PloS One
https://www.readbyqxmd.com/read/28152383/htlv-1-tax-activates-hiv-1-transcription-in-latency-models
#16
Victor Emmanuel Viana Geddes, Diego Pandeló José, Fabio E Leal, Douglas F Nixon, Amilcar Tanuri, Renato Santana Aguiar
HIV-1 latency is a major obstacle to HIV-1 eradication. Coinfection with HTLV-1 has been associated with faster progression to AIDS. HTLV-1 encodes the transactivator Tax which can activate both HTLV-1 and HIV-1 transcription. Here, we demonstrate that Tax activates HIV transcription in latent CD4(+) T cells. Tax promotes the activation of P-TEFb, releasing CDK9 and Cyclin T1 from inactive forms, promoting transcription elongation and reactivation of latent HIV-1. Tax mutants lacking interaction with the HIV-1-LTR promoter were not able to activate P-TEFb, with no subsequent activation of latent HIV...
January 30, 2017: Virology
https://www.readbyqxmd.com/read/28108460/enhancer-remodeling-during-adaptive-bypass-to-mek-inhibition-is-attenuated-by-pharmacologic-targeting-of-the-p-tefb-complex
#17
Jon S Zawistowski, Samantha M Bevill, Daniel R Goulet, Timothy J Stuhlmiller, Adriana S Beltran, Jose F Olivares-Quintero, Darshan Singh, Noah Sciaky, Joel S Parker, Naim U Rashid, Xin Chen, James S Duncan, Martin C Whittle, Steven P Angus, Sara Hanna Velarde, Brian T Golitz, Xiaping He, Charlene Santos, David B Darr, Kristalyn Gallagher, Lee M Graves, Charles M Perou, Lisa A Carey, H Shelton Earp, Gary L Johnson
Targeting the dysregulated BRAF-MEK-ERK pathway in cancer has increasingly emerged in clinical trial design. Despite clinical responses in specific cancers using inhibitors targeting BRAF and MEK, resistance develops often involving nongenomic adaptive bypass mechanisms. Inhibition of MEK1/2 by trametinib in patients with triple-negative breast cancer (TNBC) induced dramatic transcriptional responses, including upregulation of receptor tyrosine kinases (RTK) comparing tumor samples before and after one week of treatment...
March 2017: Cancer Discovery
https://www.readbyqxmd.com/read/28102758/p-tefb-finding-its-ways-to-release-promoter-proximally-paused-rna-polymerase-ii
#18
You Li, Min Liu, Lin-Feng Chen, Ruichuan Chen
The release of a paused Pol II depends on the recruitment of P-TEFb. Recent studies showed that both active P-TEFb and inactive P-TEFb (7SK snRNP) can be recruited to the promoter regions of global genes by different mechanisms. Here, we summarize the recent advances on these distinct recruitment mechanisms.
January 19, 2017: Transcription
https://www.readbyqxmd.com/read/28077616/different-modes-of-enhancer-specific-regulation-by-runt-and-even-skipped-during-drosophila-segmentation
#19
Saiyu Hang, J Peter Gergen
The initial metameric expression of the Drosophila sloppy paired 1 (slp1) gene is controlled by two distinct cis-regulatory DNA elements that interact in a nonadditive manner to integrate inputs from transcription factors encoded by the pair-rule segmentation genes. We performed chromatin immunoprecipitation on reporter genes containing these elements in different embryonic genotypes to investigate the mechanism of their regulation. The distal early stripe element (DESE) mediates both activation and repression by Runt...
March 1, 2017: Molecular Biology of the Cell
https://www.readbyqxmd.com/read/28062857/positive-feedback-loop-mediated-by-protein-phosphatase-1%C3%AE-mobilization-of-p-tefb-and-basal-cdk1-drives-androgen-receptor-in-prostate-cancer
#20
Xiaming Liu, Yanfei Gao, HuiHui Ye, Sean Gerrin, Fen Ma, Yiming Wu, Tengfei Zhang, Joshua Russo, Changmeng Cai, Xin Yuan, Jihong Liu, Shaoyong Chen, Steven P Balk
P-TEFb (CDK9/cyclin T) plays a central role in androgen receptor (AR)-mediated transactivation by phosphorylating both RNA polymerase 2 complex proteins and AR at S81. CDK9 dephosphorylation mobilizes P-TEFb from an inhibitory 7SK ribonucleoprotein complex, but mechanisms targeting phosphatases to P-TEFb are unclear. We show that AR recruits protein phosphatase 1α (PP1α), resulting in P-TEFb mobilization and CDK9-mediated AR S81 phosphorylation. This increased pS81 enhances p300 recruitment, histone acetylation, BRD4 binding and subsequent further recruitment of P-TEFb, generating a positive feedback loop that sustains transcription...
April 20, 2017: Nucleic Acids Research
keyword
keyword
74753
1
2
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read
×

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"