RNA polymerase

Bài giảng Sinh học phân tử: Chương 4 "Quá trình phiên mã ở Prokaryote" trình bày những nội dung cụ thể sau: Quá trình phiên mã ở Prokaryote, RNA polymerase, cấu trúc của Holoenzyme, sự gắn RNA Polymerase, khởi đầu phiên mã (Initiation),...và các nội dung liên quan khác. Mời các bạn cùng tham khảo.

21p hihihaha2 03-12-2016 98 8   Download

Bài giảng Sinh học phân tử 1: Chương 6 Cơ chế phiên mã, cung cấp cho người học những kiến thức như: Mối quan hệ giữa kiểu gen và kiểu hình; Lý thuyết trung tâm – Central dogma; Đặc điểm cấu tạo của enzyme RNA polymerase;... Mời các bạn cùng tham khảo!

51p caphesuadathemmatong 25-11-2021 32 3   Download

Enzyme sao chép một axit nucleic: Quá trình sao chép chuỗi axit nucleic tức là tổng hợp một chuỗi DNA hoặc RNA được tiến hành theo nguyên tắc bổ sung và đối song song. Việc thêm một nucleotide mới được tiến hành theo hướng 5’ → 3’. 1- Enzyme sao chép DNA → DNA Là các enzyme DNA-polymerase I, enzyme T4 DNA-polymerase, Taq polymerase tổng hợp chuỗi DNA từ một khuôn DNA hay còn gọi "enzyme phụ thuộc DNA".

5p butmaulam 23-09-2013 120 8   Download

The plastid transcription kinase (PTK), a component of the major RNA polymerase complex from mustard chloroplasts, has been implicated in redox-mediated regulation of plastid gene expression. A cloning strategy to define the PTK gene(s) resulted in the isolation of a full-length cDNA for a protein with overall high homology with the a subunit of cytosolic casein kinase (CK2) that contained an N-terminal extension for a putative plastid transit peptide.

9p system191 01-06-2013 46 4   Download

We have analyzed the response of a number of human cell lines to treatment with antisense oligodeoxynucleotides (ODNs) directed against RNA polymerase II, replication protein A, and Ha-ras. ODN-delivery to the cells was liposome-mediated or via electroporation, which resulted in di€erent intracellular locations of the ODNs. The ODN-mediated target mRNA reduction varied consider-ably between the cell lines.

10p research12 23-04-2013 41 3   Download

Minichromosomemaintenance (MCM) proteins are part of the replication licensing factor (RLF-M), which limits the initiationofDNAreplication to once per cell cycle.We have previously reported that higher order complexes of mam-malian pol II and general pol II transcription factors, referred to as pol II holoenzyme, also contain MCM pro-teins. In the present study we have analyzed in detail the interaction between MCM2 and pol II holoenzyme. N- and C- terminal deletions were introduced into epitope-tagged MCM2 and the truncated proteins were transiently expressed in 293 cells. ...

11p tumor12 22-04-2013 39 3   Download

Phosphorylation of RNA polymerase II’s largest subunit C-terminal domain (CTD) is a key event during mRNA metabolism. Numerous enzymes, including cell cycle-dependent kinases and TFIIF-dependent phosphatases tar-get the CTD. However, the repetitive nature of the CTD prevents determination of phosphorylated sites by conven-tional biochemistry methods. Fortunately, a panel of monoclonal antibodies is available that distinguishes between phosphorylated isoforms of RNA polymerase II’s (RNAP II) largest subunit....

12p tumor12 20-04-2013 49 2   Download

The transcription patterns of 64 linear double stranded DNA templates obtained with T7 RNA polymerase were investigated. These templates consisted of 17 nucleotide-long sequences under the control of the minimal bac-teriophage T7 promoter and represented all possible combinations of nucleotides at positions +8, +10 and +11.

8p tumor12 20-04-2013 33 5   Download

Classical swine fever virus nonstructural protein 5B (NS5B) encodes an RNA-dependent RNA polymerase, a key enzyme of the viral replication complex. To better under-stand the initiation of viral RNA synthesis and to establish anin vitroreplication system, a recombinant NS5B protein, lacking the C-terminal 24-amino acid hydrophobic domain, was expressed inEscherichia coli.

10p fptmusic 12-04-2013 47 4   Download

In our attempt to obtain further information on the replication mechanism of the hepatitis C virus (HCV), we have studied the role of sequences at the 3¢-end of HCV minus-strand RNA in the initiation of synthesis of the viral genome by viral RNA-dependent RNA polymerase (RdRp). In this report, we investigated the template and binding properties of mutated and deleted RNA fragments of the 3¢-end of the minus-strand HCV RNA in the presence of viral polymerase.

15p fptmusic 11-04-2013 54 3   Download

There is still a controversy over the mechanism of promoter DNA strand separation upon open transcription complex (RPo) formation by Escheri-chia coli RNA polymerase: is it a single or a stepwise process controlled by Mg 2+ ions and temperature? To resolve this question, the kinetics of pseudo-first-order oxidation of thymine residues by KMnO4 in the )11…+2 DNA region of RPo at thekPRpromoter was examined under single-hit conditions as a function of temperature (13–37
C) in the absence or presence of 10 mmMgCl2....

16p awards 06-04-2013 45 2   Download

The bacterial Lsm protein, host factor I (Hfq), is an RNA chaperone involved in many types of RNA transactions such as replication and stabil-ity, control of small RNA activity and polyadenylation. In this latter case, Hfq stimulates poly(A) synthesis and binds poly(A) tails that it protects from exonucleolytic degradation. We show here, that there is a correlation between Hfq binding to the 3¢ end of an RNA molecule and its ability to stimulate RNA elongation catalyzed by poly(A)polymerase I.

0p awards 05-04-2013 27 1   Download

BacterialRNApolymerase (RNAP) is the central enzyme of gene expression that is responsible for the synthesis of all types of cellular RNAs. The process of transcription is accompanied by complex structural rearrangements of RNAP. Despite the recent progress in structural studies of RNAP, detailed mechanisms of conformational changes of RNAP that occur at different stages of transcription remain unknown.

11p awards 05-04-2013 42 2   Download

TheNS5Bproteinof the classical swine fever virus (CSFV) is the RNA-dependent RNA polymerase of the virus and is able to catalyze the viral genome replication. The 3¢ un-translated region is most likely involved in regulation of the Pestivirusgenome replication. However, little is known about the interaction between the CSFV NS5B protein and the viral genome.We used different RNA templates derived fromthe plus-strand viral genome, or theminus-strand viral genome and the CSFV NS5B protein obtained from the Escherichia coliexpression system to address this problem....

9p awards 05-04-2013 46 5   Download

GE23077, a novel microbial metabolite recently isolated from Actinomadurasp. culture media, is a potent and selective inhibitor of bacterial RNApolymerase (RNAP). It inhibitsGram-positive (Bacillus subtilis) andGram-negative (Escherichia coli)RNAPs with IC50 values (i.e. the concen-tration at which the enzyme activity is inhibited by 50%) in the 10 )8 Mrange, whereas it is not active onE. coliDNA polymerase or on eukaryotic (wheat germ) RNAP II (IC50 values10 )4 Min both cases).

0p awards 05-04-2013 56 2   Download

RNA polymerase II (RNAPII) requires a set of general transcription factors )TFIIA, TFIIB, TFIID, TFIIE, TFIIF and TFIIH)to initiate transcription from a gene promoterin vitro. General transcription factors have been isolated from Saccharomyces cerevisiae,rat, human and Drosophila,and their corresponding cDNAs have been cloned. In this report, we describe a reconstitutedin vitro transcription system that consists of the following prepara-tions of factors from the yeastSchizosaccharomyces pombe: affinity-purified RNAPII, TFIIH, and recombinant TBP, TFIIB, TFIIE and TFIIF. ...

12p dell39 03-04-2013 62 3   Download

The C-terminal domain (CTD) of the largest subunit of RNA polymerase II plays critical roles in the initiation, elongation and processing of primary transcripts. These activities are at least partially regulated by the phosphory-lation of the CTDby three cyclin-dependent protein kinases (CDKs), namely CDK7, CDK8 and CDK9. In this study, we systematically compared the phosphorylation of differ-ent recombinant CTD substrates by recombinant CDK7/ CycH/MAT1, CDK8/CycCandCDK9/CycT1 kinases.We showed that CDK7, CDK8 and CDK9 produce different patterns of phosphorylation of the CTD. ...

11p dell39 03-04-2013 45 3   Download

DNA polymeraseeco-operates with polymerasesaanddin the replicative DNA synthesis of eukaryotic cells. We describe here a specific physical interaction between DNA polymerase eand RNA polymerase II, evidenced by reciprocal immunoprecipitation experiments. The interacting RNA polymerase II was the hyperphosphorylated IIO form implicated in tran-

15p inspiron33 23-03-2013 44 3   Download

In the first half of the talk, the current state of our ongoing structure-function analysis of the mRNA transcription cycle will be dis-cussed. The crystallographic structures of the complete 12-subunit RNA polymerase II in free form and with bound DNA and RNA have been determined as atomic models. The structure of the complete Pol II elongation complex bound by the transcript cleavage factor TFIIS explained how Pol II uses a single tunable active site for both RNA synthesis and RNA cleavage.

12p galaxyss3 19-03-2013 43 4   Download

Symposia Lectures Monday Monday, July 9, 2007 A2-L1 J. Diffley No abstract available. A2-L2 Molecular bioimaging of gene transcription P. Cramer Gene Center, Munich, GERMANY In the first half of the talk, the current state of our ongoing structure-function analysis of the mRNA transcription cycle will be discussed. The crystallographic structures of the complete 12-subunit RNA polymerase II in free form and with bound DNA and RNA have been determined as atomic models.

13p galaxyss3 19-03-2013 38 2   Download