Gene expression Gene expression In genetics, the 3' UTR (read as three prime untranslated region) is a particular section of messenger RNA ( mRNA). ...more on Wikipedia about "3' UTR"
An activator, is a DNA-binding protein that regulates one or more genes by increasing the rate of transcription. ...more on Wikipedia about "Activator (genetics)"
Alternative splicing is the process that occurs in eukaryotes in which the splicing process of a pre-mRNA can lead to different ripe mRNA molecules and therefore to different proteins. Also viruses have adapted to this biochemical process when using the protein biosynthesis apparatus. ...more on Wikipedia about "Alternative splicing"
Anisomycin is an antibiotic produced by Streptomyces griseolus which can arrest gene expression by inhibiting protein synthesis. It can also activate stress-activated protein kinases, MAP kinase and other signal transduction pathways. Anisomycin is inactive against bacteria. Partial inhibition of DNA synthesis occurs at anisomycin concentrations that effect 95% inhibition of protein synthesis mode of action of anisomycin ...more on Wikipedia about "Anisomycin"
A basic-helix-loop-helix (bHLH) is a protein structural motif that characterizes a family of transcription factors. The motif is characterized by two α helices connected by a loop. Transcription factors of this type are typically dimeric, each with one helix containing basic amino acid residues that facilitate DNA binding. One helix is typically smaller and due to the flexibility of the loop, allows dimerization by folding and packing against another helix. The larger helix typically contains the DNA binding regions. BHLH proteins typically bind to a consensus sequence called an E-box, CANNTG. The canonical E-box is CACGTG, however some bHLH transcription factors bind to different sequences, which are often similar to the E-box. Examples of bHLH transcription factors include: ...more on Wikipedia about "Basic-helix-loop-helix"
The CCAAT box is a promoter element in some genes located about 75-80 base pairs upstream of the start site for transcription. It is an invariant DNA sequence at about minus 70 base pairs from the origin of transcription in many eukaryotic promoters.Genes that have this element seem to require it for the gene to be transcribed in sufficient quantities. It is frequently absent from genes that encode proteins used in virtually all cells. ...more on Wikipedia about "CCAAT box"
Regulation has to be specific to particular genes. Regulatory systems, therefore, need to have something that is physically linked to a target gene as an address to tell the trans-acting factors that the gene they are linked to is something that should be regulated. These sequences, which can be in the DNA, the RNA or the protein are called cis-acting elements if their action depends on their being physically linked to the regulatory target. ...more on Wikipedia about "Cis-acting element"
A constitutive gene is a gene that is transcribed continually. ...more on Wikipedia about "Constitutive gene"
Dicistronic is the term used to describe an mRNA that encodes for two genes, usually with a non-coding region in the middle called the intergenic region. It is most common in viral genomes. ...more on Wikipedia about "Dicistronic"
A DNA microarray is a collection of microscopic DNA spots attached to a solid surface, such as glass, plastic or silicon chip forming an array. Scientists use DNA microarrays to measure the expression levels of large numbers of genes simultaneously. The affixed DNA segments are known as probes (although some sources will use different nomenclature), thousands of which can be used in a single DNA microarray. Microarray technology evolved from Southern Blotting, where fragmented DNA is attached to a substrate and then probed with a known gene or fragment. Measuring gene expression using microarrays is relevant to many areas of biology and medicine, such as studying treatments, disease and developmental stages. ...more on Wikipedia about "DNA microarray"
In genetics, an enhancer is a short region of DNA that can be bound with proteins (namely, the trans-acting factors, much like a set of transcription factors) to enhance transcription levels of genes (hence the name) in a gene-cluster. An enhancer does not need to be particularly close to the genes it acts on, but it is on the same chromosome. (An exception to this rule was published in a 1990 article in Science, where researchers Wedel, et. al., made two linked circles of DNA, one circle with the enhancer sequence and the other with its promoter. An abstract can be found here .) ...more on Wikipedia about "Enhancer"
Exon trapping is a molecular biology technique to identify potential exons in a fragment of eucaryote DNA of unknown intron- exon structure. This is done to determine if the fragment is part of an expressed gene. ...more on Wikipedia about "Exon trapping"
An expressed sequence tag or EST is a short sub-sequence of a transcribed protein-coding or non-protein coding DNA sequence. It was originally intended as a way to identify gene transcripts, but has since been instrumental in gene discovery and sequence determination. An EST is produced by one-shot sequencing of a cloned mRNA, and the resulting sequence is a relatively low quality fragment whose length is limited by current technology to approximately 500 to 800 nucleotides. ESTs are also a useful resource for designing probes for DNA microarrays used to determine gene expression. ...more on Wikipedia about "Expressed sequence tag"
An expression vector is a relatively small DNA molecule that is used to introduce and express a specific gene into a target cell. Once the expression vector is inside the cell, the protein that is encoded by the gene is produced by the cellular transcription and translation machinery. ...more on Wikipedia about "Expression vector"
http://www.shortopedia.com - now! Gene_expression
Gene expression (also protein expression or often simply expression) is the process by which a gene's information is converted into the structures and functions of a cell. ...more on Wikipedia about "Gene expression"
A gene regulatory network (also called a GRN or genetic regulatory network) is a collection of DNA segments in a cell which ...more on Wikipedia about "Gene regulatory network"
The genetic code is a set of rules that maps DNA sequences to proteins in the living cell, and is employed in the process of protein synthesis. Nearly all living things use the same genetic code, called the standard genetic code, although a few organisms use minor variations of the standard code. ...more on Wikipedia about "Genetic code"
A housekeeping gene is a constitutive gene that is transcribed at low basal levels continually. The housekeeping gene's products are typically needed for maintenance of the cell. ...more on Wikipedia about "Housekeeping gene"
Hypoxia inducible factors (HIFs) are transcription factors that respond to changes in available oxygen in the cellular environment, specifically to decreases in oxygen, or hypoxia. Many organisms express the highly conserved transcriptional complex HIF-1, which is a heterodimer composed of an alpha and beta subunit, the latter being a constituitively expressed aryl hydrocarbon receptor nuclear translocator (ARNT). HIF-1 belongs to the PAS subfamily of the basic-helix-loop-helix (bHLH) family of transcription factors. The alpha subunit of HIF-1 is a target for prolyl hydroxylation by HIF prolyl-hydroxylase, which makes HIF-1 alpha a target for degradation by the E3 ubiquitin ligase complex. This only occurs in normoxic conditions. In hypoxic conditions, HIF prolyl-hydroxylase is inhibited since it utilizes oxygen as a cosubstrate. Hypoxia also results in a build up of succinate, due to inhibition of the electron transport chain in the mitochondria. The build up of succinate further inhibits HIF prolyl-hydroxylase action since it is an end product of HIF hydoxylation. ...more on Wikipedia about "Hypoxia inducible factors"
ICSBP: Interferon Consensus Sequence-binding protein or Interferon Regulatory Factor 8 (IRF-8). It is a transcription factor that plays critical roles in the regulation of lineage commitment and in myeloid cell maturation. ...more on Wikipedia about "Icsbp"
Genomic imprinting is the phenomenon whereby a small subset of all the genes in our genome are expressed according to their parent of origin. Some imprinted genes are expressed from a maternally inherited chromosome and silenced on the paternal chromosome; while other imprinted genes show the opposite expression pattern and are only expressed from a paternally inherited chromosome. Contrary to expectation, 'imprints' can act as a silencer or an activator for imprinted genes. ...more on Wikipedia about "Imprinting (genetics)" Fast www.shortopedia.com
An inducible gene is a gene whose expression is either responsive to environmental change or dependent on the position of the cell cycle. ...more on Wikipedia about "Inducible gene"
Introns (for intragenic regions) are sections of DNA within a gene that do not encode part of the protein that the gene produces, and are spliced out of the mRNA that is transcribed from the gene before it is translated. Introns exist mainly (but not only) in eukaryotic cells. The regions of a gene that remain in the spliced mRNA are called exons. The number and length of introns varies widely among species. For example, the pufferfish Takifugu rubripes has little intronic DNA. Mammals and flowering plants, on the other hand, have numerous introns, which are often much longer than the nearby exons. ...more on Wikipedia about "Intron"
The lac operon is an operon required for the transport and metabolism of lactose in Escherichia coli and some other enteric bacteria. It consists of three adjacent structural genes, a promoter, a terminator, and an operator. The lac operon is regulated by several factors including the availability of glucose and of lactose. Gene regulation of the lac operon was the first genetic regulatory mechanism to be elucidated and is often used as the canonical example of prokaryotic gene regulation. ...more on Wikipedia about "Lac operon"
The lac repressor is a DNA-binding protein which inhibits the expression of genes coding for proteins involved in the metabolism of lactose in bacteria. This occurs in the absence of lactose, presumably so that the organism doesn't waste amino acids producing unnecessary proteins. When lactose becomes available, it is converted into allolactose, which inhibits the Lac repressor's DNA binding ability. ...more on Wikipedia about "Lac repressor"
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