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DHX29
DExH-box helicase 29 (DHX29) is a 155 kDa protein that in humans is encoded by the DHX29 gene. Function This gene encodes a member of the DEAH (Asp-Glu-Ala-His) subfamily of proteins, part of the DEAD (Asp-Glu-Ala-Asp) box family of RNA helicases. The encoded protein functions in translation initiation, and is specifically required for ribosomal scanning across stable mRNA secondary structures during initiation codon selection. This protein may also play a role in sensing virally derived cytosolic nucleic acids. Knockdown of this gene results in reduced protein translation and impaired proliferation of cancer cells. Interactions DHX29 has been shown to interact with the eukaryotic small ribosomal subunit (40S) and eIF3. See also *Eukaryotic translation Eukaryotic translation is the biological process by which messenger RNA is Translation (biology), translated into proteins in eukaryotes. It consists of four phases: initiation, elongation, termination, and recapping. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
EIF3
Eukaryotic initiation factor 3 (eIF3) is a multiprotein complex that functions during the initiation phase of eukaryotic translation. It is essential for most forms of Eukaryotic translation#Cap-dependent initiation, cap-dependent and Eukaryotic translation#cap-independent, cap-independent translation initiation. In humans, eIF3 consists of 13 nonidentical subunits (eIF3a-m) with a combined molecular weight of ~800 kDa, making it the largest Eukaryotic initiation factor, translation initiation factor. The eIF3 complex is broadly conserved across eukaryotes, but the conservation of individual subunits varies across organisms. For instance, while most mammalian eIF3 complexes are composed of 13 subunits, Saccharomyces cerevisiae, budding yeast's eIF3 has only six subunits (eIF3a, b, c, g, i, j). Function eIF3 stimulates nearly all steps of translation initiation. eIF3 also appears to participate in other phases of translation, such as recycling, where it promotes the splitting of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eukaryotic Translation
Eukaryotic translation is the biological process by which messenger RNA is Translation (biology), translated into proteins in eukaryotes. It consists of four phases: initiation, elongation, termination, and recapping. Initiation Translation initiation is the process by which the ribosome and its associated factors bind to an mRNA and are assembled at the start codon. This process is defined as either cap-dependent, in which the ribosome binds initially at the 5' cap and then travels to the stop codon, or as cap-independent, where the ribosome does not initially bind the 5' cap. Cap-dependent initiation Initiation of translation usually involves the interaction of certain key proteins, the initiation factors, with a special tag bound to the 5'-end of an mRNA molecule, the 5' cap, as well as with the 5' UTR. These proteins bind the small (40S) ribosome, ribosomal subunit and hold the mRNA in place. Eukaryotic initiation factor 3, eIF3 is associated with the 40S ribosomal subunit ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Protein
Proteins are large biomolecules and macromolecules that comprise one or more long chains of amino acid residue (biochemistry), residues. Proteins perform a vast array of functions within organisms, including Enzyme catalysis, catalysing metabolic reactions, DNA replication, Cell signaling, responding to stimuli, providing Cytoskeleton, structure to cells and Fibrous protein, organisms, and Intracellular transport, transporting molecules from one location to another. Proteins differ from one another primarily in their sequence of amino acids, which is dictated by the Nucleic acid sequence, nucleotide sequence of their genes, and which usually results in protein folding into a specific Protein structure, 3D structure that determines its activity. A linear chain of amino acid residues is called a polypeptide. A protein contains at least one long polypeptide. Short polypeptides, containing less than 20–30 residues, are rarely considered to be proteins and are commonly called pep ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gene
In biology, the word gene has two meanings. The Mendelian gene is a basic unit of heredity. The molecular gene is a sequence of nucleotides in DNA that is transcribed to produce a functional RNA. There are two types of molecular genes: protein-coding genes and non-coding genes. During gene expression (the synthesis of Gene product, RNA or protein from a gene), DNA is first transcription (biology), copied into RNA. RNA can be non-coding RNA, directly functional or be the intermediate protein biosynthesis, template for the synthesis of a protein. The transmission of genes to an organism's offspring, is the basis of the inheritance of phenotypic traits from one generation to the next. These genes make up different DNA sequences, together called a genotype, that is specific to every given individual, within the gene pool of the population (biology), population of a given species. The genotype, along with environmental and developmental factors, ultimately determines the phenotype ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
DExD/H Box Proteins
DEAD box proteins are involved in an assortment of metabolic processes that typically involve RNAs, but in some cases also other nucleic acids. They are highly conserved in nine motifs and can be found in most prokaryotes and eukaryotes, but not all. Many organisms, including humans, contain DEAD-box (SF2) helicases, which are involved in RNA metabolism. DEAD box family DEAD box proteins were first brought to attention in the late 1980s in a study that looked at a group of NTP binding sites that were similar in sequence to the eIF4A RNA helicase sequence. The results of this study showed that these proteins (p68, SrmB, MSS116, vasa, PL10, mammalian eIF4A, yeast eIF4A) involved in RNA metabolism had several common elements. There were nine common sequences found to be conserved amongst the studied species, which is an important criterion of the DEAD box family. The nine conserved motif from the N-terminal to the C-terminal are named as follows: Q-motif, motif 1, motif 1a, moti ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Helicase
Helicases are a class of enzymes that are vital to all organisms. Their main function is to unpack an organism's genetic material. Helicases are motor proteins that move directionally along a nucleic double helix, separating the two hybridized nucleic acid strands (hence '' helic- + -ase''), via the energy gained from ATP hydrolysis. There are many helicases, representing the great variety of processes in which strand separation must be catalyzed. Approximately 1% of eukaryotic genes code for helicases. The human genome codes for 95 non-redundant helicases: 64 RNA helicases and 31 DNA helicases. Many cellular processes, such as DNA replication, transcription, translation, recombination, DNA repair and ribosome biogenesis involve the separation of nucleic acid strands that necessitates the use of helicases. Some specialized helicases are also involved in sensing viral nucleic acids during infection and fulfill an immunological function. Genetic mutations that affect helicase ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
MRNA
In molecular biology, messenger ribonucleic acid (mRNA) is a single-stranded molecule of RNA that corresponds to the genetic sequence of a gene, and is read by a ribosome in the process of Protein biosynthesis, synthesizing a protein. mRNA is created during the process of Transcription (biology), transcription, where an enzyme (RNA polymerase) converts the gene into primary transcript mRNA (also known as pre-mRNA). This pre-mRNA usually still contains introns, regions that will not go on to code for the final amino acid sequence. These are removed in the process of RNA splicing, leaving only exons, regions that will encode the protein. This exon sequence constitutes mature mRNA. Mature mRNA is then read by the ribosome, and the ribosome creates the protein utilizing amino acids carried by transfer RNA (tRNA). This process is known as Translation (biology), translation. All of these processes form part of the central dogma of molecular biology, which describes the flow of geneti ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Codon
Genetic code is a set of rules used by living cells to translate information encoded within genetic material (DNA or RNA sequences of nucleotide triplets or codons) into proteins. Translation is accomplished by the ribosome, which links proteinogenic amino acids in an order specified by messenger RNA (mRNA), using transfer RNA (tRNA) molecules to carry amino acids and to read the mRNA three nucleotides at a time. The genetic code is highly similar among all organisms and can be expressed in a simple table with 64 entries. The codons specify which amino acid will be added next during protein biosynthesis. With some exceptions, a three-nucleotide codon in a nucleic acid sequence specifies a single amino acid. The vast majority of genes are encoded with a single scheme (see the RNA codon table). That scheme is often called the canonical or standard genetic code, or simply ''the'' genetic code, though variant codes (such as in mitochondria) exist. History Efforts to understan ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Translation (biology)
In biology, translation is the process in living Cell (biology), cells in which proteins are produced using RNA molecules as templates. The generated protein is a sequence of amino acids. This sequence is determined by the sequence of nucleotides in the RNA. The nucleotides are considered three at a time. Each such triple results in the addition of one specific amino acid to the protein being generated. The matching from nucleotide triple to amino acid is called the genetic code. The translation is performed by a large complex of functional RNA and proteins called ribosomes. The entire process is called gene expression. In translation, messenger RNA (mRNA) is decoded in a ribosome, outside the nucleus, to produce a specific amino acid chain, or polypeptide. The polypeptide later protein folding, folds into an Activation energy, active protein and performs its functions in the cell. The polypeptide can also start folding during protein synthesis. The ribosome facilitates decoding ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eukaryotic Small Ribosomal Subunit (40S)
The eukaryotic small ribosomal subunit (40S) is the smaller subunit of the 80S, eukaryotic 80S ribosomes, with the other major component being the eukaryotic large ribosomal subunit (60S), large ribosomal subunit (60S). The "40S" and "60S" names originate from the convention that ribosomal particles are denoted according to their sedimentation coefficients in Svedberg, Svedberg units. It is structurally and functionally related to the 30S, 30S subunit of 70S, 70S prokaryotic ribosomes. However, the 40S subunit is much larger than the prokaryotic 30S subunit and contains many additional protein segments, as well as rRNA expansion segments. Function The 40S subunit contains the decoding center which monitors the complementarity of tRNA and mRNA in protein translation. It is the largest component of several translation initiation complexes, including the 43S and 48S preinitiation complexes (PICs), being bound by several eukaryotic initiation factors, including eIF1, eIF1AX, eIF1A, and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
