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Mnt IRES
The Mnt internal ribosome entry site (Internal ribosome entry site, IRES) is an cis-regulatory element, RNA element. Mnt is a transcriptional repressor related to the Myc/Mad family of transcription factors. It is thought that this IRES allows efficient Mnt synthesis when cap-dependent translation initiation is reduced. See also *N-myc internal ribosome entry site (IRES), N-myc IRES *Tobamovirus internal ribosome entry site (IRES), Tobamovirus IRES *TrkB IRES References External links * Cis-regulatory RNA elements {{molecular-cell-biology-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Secondary Structure
Protein secondary structure is the three dimensional conformational isomerism, form of ''local segments'' of proteins. The two most common Protein structure#Secondary structure, secondary structural elements are alpha helix, alpha helices and beta sheets, though beta turns and omega loops occur as well. Secondary structure elements typically spontaneously form as an intermediate before the protein protein folding, folds into its three dimensional protein tertiary structure, tertiary structure. Secondary structure is formally defined by the pattern of hydrogen bonds between the Amine, amino hydrogen and carboxyl oxygen atoms in the peptide backbone chain, backbone. Secondary structure may alternatively be defined based on the regular pattern of backbone Dihedral angle#Dihedral angles of proteins, dihedral angles in a particular region of the Ramachandran plot regardless of whether it has the correct hydrogen bonds. The concept of secondary structure was first introduced by Kaj Ulrik ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sequence Conservation
In evolutionary biology, conserved sequences are identical or similar sequences in nucleic acids ( DNA and RNA) or proteins across species ( orthologous sequences), or within a genome ( paralogous sequences), or between donor and receptor taxa ( xenologous sequences). Conservation indicates that a sequence has been maintained by natural selection. A highly conserved sequence is one that has remained relatively unchanged far back up the phylogenetic tree, and hence far back in geological time. Examples of highly conserved sequences include the RNA components of ribosomes present in all domains of life, the homeobox sequences widespread amongst Eukaryotes, and the tmRNA in Bacteria. The study of sequence conservation overlaps with the fields of genomics, proteomics, evolutionary biology, phylogenetics, bioinformatics and mathematics. History The discovery of the role of DNA in heredity, and observations by Frederick Sanger of variation between animal insulins in 1949, promp ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cis-regulatory Element
''Cis''-regulatory elements (CREs) or ''Cis''-regulatory modules (CRMs) are regions of non-coding DNA which regulate the transcription of neighboring genes. CREs are vital components of genetic regulatory networks, which in turn control morphogenesis, the development of anatomy, and other aspects of embryonic development, studied in evolutionary developmental biology. CREs are found in the vicinity of the genes that they regulate. CREs typically regulate gene transcription by binding to transcription factors. A single transcription factor may bind to many CREs, and hence control the expression of many genes ( pleiotropy). The Latin prefix ''cis'' means "on this side", i.e. on the same molecule of DNA as the gene(s) to be transcribed. CRMs are stretches of DNA, usually 100–1000 DNA base pairs in length, where a number of transcription factors can bind and regulate expression of nearby genes and regulate their transcription rates. They are labeled as ''cis'' because they are ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Internal Ribosome Entry Site
An internal ribosome entry site, abbreviated IRES, is an RNA element that allows for translation initiation in a cap-independent manner, as part of the greater process of protein synthesis. In eukaryotic translation, initiation typically occurs at the 5' end of mRNA molecules, since 5' cap recognition is required for the assembly of the initiation complex. The location for IRES elements is often in the 5'UTR, but can also occur elsewhere in mRNAs. History IRES sequences were first discovered in 1988 in the poliovirus (PV) and encephalomyocarditis virus (EMCV) RNA genomes in the labs of Nahum Sonenberg and Eckard Wimmer, respectively. They are described as distinct regions of RNA molecules that are able to recruit the eukaryotic ribosome to the mRNA. This process is also known as cap-independent translation. It has been shown that IRES elements have a distinct secondary or even tertiary structure, but similar structural features at the levels of either primary or secondary structur ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eukaryota
Eukaryotes () are organisms whose Cell (biology), cells have a cell nucleus, 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-domain system, 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), Asgard archaea. This implies that there are only Two-domain system, 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 (ecology), 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 cell, flagellated phagotrophs. The ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cis-regulatory Element
''Cis''-regulatory elements (CREs) or ''Cis''-regulatory modules (CRMs) are regions of non-coding DNA which regulate the transcription of neighboring genes. CREs are vital components of genetic regulatory networks, which in turn control morphogenesis, the development of anatomy, and other aspects of embryonic development, studied in evolutionary developmental biology. CREs are found in the vicinity of the genes that they regulate. CREs typically regulate gene transcription by binding to transcription factors. A single transcription factor may bind to many CREs, and hence control the expression of many genes ( pleiotropy). The Latin prefix ''cis'' means "on this side", i.e. on the same molecule of DNA as the gene(s) to be transcribed. CRMs are stretches of DNA, usually 100–1000 DNA base pairs in length, where a number of transcription factors can bind and regulate expression of nearby genes and regulate their transcription rates. They are labeled as ''cis'' because they are ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Transcription Factor
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 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
N-myc Internal Ribosome Entry Site (IRES)
The N-myc internal ribosome entry site (IRES) is an RNA element found in the n-myc gene. The myc family of genes when expressed are known to be involved in the control of cell growth, differentiation and apoptosis. n-myc mRNA has an alternative method of translation via an internal ribosome entry site where ribosomes are recruited to the IRES located in the 5' UTR thus bypassing the typical eukaryotic cap-dependent translation pathway. See also *Mnt IRES * Tobamovirus IRES *TrkB IRES The TrkB internal ribosome entry site (IRES) is an RNA element which is present in the 5' UTR sequence of the mRNA. TrkB is a neurotrophin receptor which is essential for the development and maintenance of the nervous system. The internal ribosom ... References External links * Cis-regulatory RNA elements {{molecular-cell-biology-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tobamovirus Internal Ribosome Entry Site (IRES)
The Tobamovirus internal ribosome entry site (IRES) is an element that allows cap and end-independent translation of mRNA in the host cell. The IRES achieves this by mediating the internal initiation of translation by recruiting a ribosomal 43S pre-initiation complex directly to the initiation codon and eliminates the requirement for the eukaryotic initiation factor, eIF4F. See also *Mnt IRES * N-myc IRES *TrkB IRES The TrkB internal ribosome entry site (IRES) is an RNA element which is present in the 5' UTR sequence of the mRNA. TrkB is a neurotrophin receptor which is essential for the development and maintenance of the nervous system. The internal ribosom ... References External links * Cis-regulatory RNA elements Tobamovirus {{molecular-cell-biology-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
TrkB IRES
The TrkB internal ribosome entry site (IRES) is an RNA element which is present in the 5' UTR sequence of the mRNA. TrkB is a neurotrophin receptor which is essential for the development and maintenance of the nervous system. The internal ribosome entry site IRES element allows cap-independent translation of TrkB which may be needed for efficient translation in neuronal dendrites. See also *Mnt IRES The Mnt internal ribosome entry site (Internal ribosome entry site, IRES) is an cis-regulatory element, RNA element. Mnt is a transcriptional repressor related to the Myc/Mad family of transcription factors. It is thought that this IRES allows eff ... * N-myc IRES * Tobamovirus IRES References External links * Cis-regulatory RNA elements {{molecular-cell-biology-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
