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General Transcription Factors
General transcription factors (GTFs), also known as basal transcriptional factors, are a class of protein transcription factors that bind to specific sites ( promoter) on DNA to activate transcription of genetic information from DNA to messenger RNA. GTFs, RNA polymerase, and the mediator (a multi-protein complex) constitute the basic transcriptional apparatus that first bind to the promoter, then start transcription. GTFs are also intimately involved in the process of gene regulation, and most are required for life. A transcription factor is a protein that binds to specific DNA sequences ( enhancer or promoter), either alone or with other proteins in a complex, to control the rate of transcription of genetic information from DNA to messenger RNA by promoting (serving as an activator) or blocking (serving as a repressor) the recruitment of RNA polymerase. As a class of protein, general transcription factors bind to promoters along the DNA sequence or form a large transcription pr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Transcription Factors
In molecular biology, a transcription factor (TF) (or sequence-specific DNA-binding factor) is a protein that controls the rate of transcription of genetic information from DNA to messenger RNA, by binding to a specific DNA sequence. The function of TFs is to regulate—turn on and off—genes in order to make sure that they are expressed in the desired cells at the right time and in the right amount throughout the life of the cell and the organism. Groups of TFs function in a coordinated fashion to direct cell division, cell growth, and cell death throughout life; cell migration and organization (body plan) during embryonic development; and intermittently in response to signals from outside the cell, such as a hormone. There are up to 1600 TFs in the human genome. Transcription factors are members of the proteome as well as regulome. TFs work alone or with other proteins in a complex, by promoting (as an activator), or blocking (as a repressor) the recruitment of RNA po ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Annual Review Of Biochemistry
''Annual Review of Biochemistry'' is an annual peer reviewed scientific journal published by Annual Reviews, a nonprofit scientific publisher. Its first volume was published in 1932, and its founding editor was J. Murray Luck. The current editor is Roger D. Kornberg. The journal focuses on molecular biology and biological chemistry review articles. As of 2022, ''Journal Citation Reports'' gives the journal an impact factor of 27.258, ranking it fifth out of 296 journals in the category "Biochemistry and Molecular Biology". History The ''Annual Review of Biochemistry'' was the creation of Stanford University chemist and professor J. Murray Luck. In 1930, Luck offered a course on current research in biochemistry to graduate students. In designing the course, he said he felt "knee-deep in trouble", as he believed he was sufficiently knowledgeable in only a few areas of biochemistry. He considered the volume of research to be overwhelming; there were 6,500 abstracts regarding bioch ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
TFIIH
Transcription factor II Human (transcription factor II H; TFIIH) is an important protein complex, having roles in transcription of various protein-coding genes and DNA nucleotide excision repair (NER) pathways. TFIIH first came to light in 1989 when general transcription factor-δ or basic transcription factor 2 was characterized as an indispensable transcription factor in vitro. This factor was also isolated from yeast and finally named as TFIIH in 1992. TFIIH consists of ten subunits, 7 of which (ERCC2/XPD, ERCC3/XPB, GTF2H1/p62, GTF2H4/p52, GTF2H2/p44, GTF2H3/p34 and GTF2H5/TTDA) form the core complex. The cyclin activating kinase-subcomplex (CDK7, MAT1, and cyclin H) is linked to the core via the XPD protein. Two of the subunits, ERCC2/XPD and ERCC3/XPB, have helicase and ATPase activities and help create the transcription bubble. In a test tube these subunits are only required for transcription if the DNA template is not already denatured or if it is supercoiled. Two ot ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
TFIIF
Transcription factor II F (TFIIF) is one of several general transcription factors that make up the RNA polymerase II preinitiation complex. TFIIF is encoded by the , , and genes. TFIIF binds to RNA polymerase II RNA polymerase II (RNAP II and Pol II) is a multiprotein complex that transcribes DNA into precursors of messenger RNA (mRNA) and most small nuclear RNA (snRNA) and microRNA. It is one of the three RNAP enzymes found in the nucleus of eukaryoti ... when the enzyme is already unbound to any other transcription factor, thus preventing it from contacting DNA outside the promoter. Furthermore, TFIIF stabilizes the RNA polymerase II while it's contacting TBP and TFIIB. See also * TFIIA * TFIIB * TFIID * TFIIE * TFIIH References External links * Molecular genetics Proteins Gene expression Transcription factors {{genetics-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
TFIIE
Transcription factor II E (TFIIE) is one of several general transcription factors that make up the RNA polymerase II preinitiation complex. It is a tetramer of two alpha and two beta chains and interacts with TAF6/TAFII80, ATF7IP, and varicella-zoster virus IE63 protein. TFIIE recruits TFIIH to the initiation complex and stimulates the RNA polymerase II C-terminal domain kinase and DNA-dependent ATPase activities of TFIIH. Both TFIIH and TFIIE are required for promoter clearance by RNA polymerase. Transcription factor II E is encoded by the GTF2E1 and GTF2E2 genes. TFIIE is thought to be involved in DNA melting Nucleic acid thermodynamics is the study of how temperature affects the nucleic acid structure of double-stranded DNA (dsDNA). The melting temperature (''Tm'') is defined as the temperature at which half of the DNA strands are in the random coil o ... at the promoter: it contains a zinc ribbon motif that can bind single stranded DNA. See also * TFIIH * TFIIB * ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
TFIID
Transcription factor II D (TFIID) is one of several general transcription factors that make up the RNA polymerase II preinitiation complex. RNA polymerase II holoenzyme is a form of eukaryotic RNA polymerase II that is recruited to the promoters of protein-coding genes in living cells. It consists of RNA polymerase II, a subset of general transcription factors, and regulatory proteins known as SRB proteins. Before the start of transcription, the transcription Factor II D (TFIID) complex binds to the core promoter DNA of the gene through specific recognition of promoter sequence motifs, including the TATA box, Initiator, Downstream Promoter, Motif Ten, or Downstream Regulatory elements. Functions * Coordinates the activities of more than 70 polypeptides required for initiation of transcription by RNA polymerase II * Binds to the core promoter to position the polymerase properly * Serves as the scaffold for assembly of the remainder of the transcription complex * Acts as a channel ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
TFIIB
Transcription factor II B (TFIIB) is a general transcription factor that is involved in the formation of the RNA polymerase II preinitiation complex (PIC) and aids in stimulating transcription initiation. TFIIB is localised to the nucleus and provides a platform for PIC formation by binding and stabilising the DNA-TBP (TATA-binding protein) complex and by recruiting RNA polymerase II and other transcription factors. It is encoded by the gene, and is homologous to archaeal transcription factor B and analogous to bacterial sigma factors. Structure TFIIB is a single 33kDa polypeptide consisting of 316 amino acids. TFIIB is made up of four functional regions: the C-terminal core domain; the B linker; the B reader and the amino terminal zinc ribbon. TFIIB makes protein-protein interactions with the TATA-binding protein (TBP) subunit of transcription factor IID, and the RPB1 subunit of RNA polymerase II. TFIIB makes sequence-specific protein-DNA interactions with the B recognit ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
TFIIA
Transcription factor TFIIA is a nuclear protein involved in the RNA polymerase II-dependent transcription of DNA. TFIIA is one of several general (basal) transcription factors ( GTFs) that are required for all transcription events that use RNA polymerase II. Other GTFs include TFIID, a complex composed of the TATA binding protein TBP and TBP-associated factors (TAFs), as well as the factors TFIIB, TFIIE, TFIIF, and TFIIH. Together, these factors are responsible for promoter recognition and the formation of a transcription preinitiation complex (PIC) capable of initiating RNA synthesis from a DNA template. Functions TFIIA interacts with the TBP subunit of TFIID and aids in the binding of TBP to TATA-box containing promoter DNA. Interaction of TFIIA with TBP facilitates formation of and stabilizes the preinitiation complex. Interaction of TFIIA with TBP also results in the exclusion of negative (repressive) factors that might otherwise bind to TBP and interfere wit ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Genes & Development
''Genes & Development'' is a peer-reviewed scientific journal covering molecular biology, molecular genetics, cell biology, and development. It was established in 1987 and is published twice monthly by Cold Spring Harbor Laboratory Press in association with The Genetics Society. According to the ''Journal Citation Reports'', the journal has a 2012 impact factor of 12.44, ranking it 14th out of 181 journals in the category "Cell Biology", third out of 40 journals in the category "Developmental Biology", and 7th out of 158 journals in the category "Genetics & Heredity". Over 1999–2004, the journal was ranked fifth in the "Molecular Biology and Genetics" category according to ''ScienceWatch'', with an average of 47 citations per paper. All issues are available online via the journal website as PDFs, with a text version additionally available from August 1997. Content over 6 months old is freely available. Since 1989, the editor-in-chief has been Terri Grodzicker (Cold Spring Harbor ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
RNA Polymerase II
RNA polymerase II (RNAP II and Pol II) is a multiprotein complex that transcribes DNA into precursors of messenger RNA (mRNA) and most small nuclear RNA (snRNA) and microRNA. It is one of the three RNAP enzymes found in the nucleus of eukaryotic cells. A 550 kDa complex of 12 subunits, RNAP II is the most studied type of RNA polymerase. A wide range of transcription factors are required for it to bind to upstream gene promoters and begin transcription. Discovery Early studies suggested a minimum of two RNAPs: one which synthesized rRNA in the nucleolus, and one which synthesized other RNA in the nucleoplasm, part of the nucleus but outside the nucleolus. In 1969, science experimentalists Robert Roeder and William Rutter definitively discovered an additional RNAP that was responsible for transcription of some kind of RNA in the nucleoplasm. The finding was obtained by the use of ion-exchange chromatography via DEAE coated Sephadex beads. The technique separated the enzymes ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eukaryotes
Eukaryotes () are organisms whose cells have a nucleus. All animals, plants, fungi, and many unicellular organisms, are Eukaryotes. They belong to the group of organisms Eukaryota or Eukarya, which is one of the three domains of life. Bacteria and Archaea (both prokaryotes) make up the other two domains. The eukaryotes are usually now regarded as having emerged in the Archaea or as a sister of the Asgard archaea. This implies that there are only two domains of life, Bacteria and Archaea, with eukaryotes incorporated among archaea. Eukaryotes represent a small minority of the number of organisms, but, due to their generally much larger size, their collective global biomass is estimated to be about equal to that of prokaryotes. Eukaryotes emerged approximately 2.3–1.8 billion years ago, during the Proterozoic eon, likely as flagellated phagotrophs. Their name comes from the Greek εὖ (''eu'', "well" or "good") and κάρυον (''karyon'', "nut" or "kernel"). Eu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Archaea
Archaea ( ; singular archaeon ) is a domain of single-celled organisms. These microorganisms lack cell nuclei and are therefore prokaryotes. Archaea were initially classified as bacteria, receiving the name archaebacteria (in the Archaebacteria kingdom), but this term has fallen out of use. Archaeal cells have unique properties separating them from the other two domains, Bacteria and Eukaryota. Archaea are further divided into multiple recognized phyla. Classification is difficult because most have not been isolated in a laboratory and have been detected only by their gene sequences in environmental samples. Archaea and bacteria are generally similar in size and shape, although a few archaea have very different shapes, such as the flat, square cells of ''Haloquadratum walsbyi''. Despite this morphological similarity to bacteria, archaea possess genes and several metabolic pathways that are more closely related to those of eukaryotes, notably for the enzymes involved ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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