gene expression

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Related to Expressed genes: transcriptional profiling

expression

 [eks-presh´un]
1. the aspect or appearance of the face as determined by the physical or emotional state.
2. the act of squeezing out or evacuating by pressure.
gene expression
1. the flow of genetic information from gene to protein.
2. the process, or the regulation of the process, by which the effects of a gene are manifested.
3. the manifestation of a heritable trait in an individual carrying the gene or genes that determine it.

gene ex·pres·sion

1. the detectable effect of a gene.
2. appearance of an inherited trait; for many genetic (for example, recessiveness, hypostasis, parastasis) and environmental (the absence of pertinent challenges) reasons, a gene may not be expressed at all. In those circumstances, it will have no impact on Darwinian evolution.

gene expression

the flow of genetic information from gene to protein; the process, or the regulation of the process, by which the effects of a gene are manifested; the manifestation of a heritable trait in an individual carrying the gene or genes that determine it.

gene expression

Genetics The process by which a gene's coded information is translated into the structures present and operating in the cell. See Gene, mRNA, Protein, RNA, Transcription, Translation, tRNA.

gene ex·pres·sion

(jēn eks-presh'ŭn)
1. The detectable effect of a gene.
2. Appearance of an inherited trait; for many reasons, a gene may not be expressed at all.

gene expression

the processes effecting the transfer of information encoded in the GENE to the functional gene product (PROTEIN or RNA). Generally, gene expression is equated with the processes of TRANSCRIPTION and TRANSLATION. However, where the gene product is RNA only transcription is involved. A gene that is expressed is an active gene.

gene

the unit of heredity most simply defined as a specific segment of DNA, usually in the order of 1000 nucleotides, that specifies a single polypeptide. Many phenotypic characteristics are determined by a single gene, while others are multigenic. Genes are specifically located in linear order along the single DNA molecule that makes up each chromosome. All eukaryotic cells contain a diploid (2n) set of chromosomes so that two copies of each gene, one derived from each parent, are present in each cell; the two copies often specify a different phenotype, i.e. the polypeptide will have a somewhat different amino acid composition. These alternative forms of gene, both within and between individuals, are called alleles. Genes determine the physical (structural genes), the biochemical (enzymes), physiological and behavioral characteristics of an animal.
The formation of gametes (sperm, ova) involves a process of meiosis, which allows crossing over between four pairs of chromosomes, two derived from each parent, which means that new forms of a particular chromosome are created. Gamete formation also results in cells (gametes) with a haploid (n) set of chromosomes that in fertilization creates a new individual, which is a recombinant of 2n chromosomes, half derived by way of the ovum from the mother and half via the spermatozoa from the father.
Changes in the nucleotide sequence of a gene, either by substitution of a different nucleotide or by deletion or insertion of other nucleotides, constitute mutations which add to the diversity of animal species by creating different alleles and can be used as a basis for genetic selection of different phenotypes. Some mutations, be they a single base change in a single gene or a major deletion, are lethal.

gene action
the way in which genes exert their effects on tissues or processes, e.g. by being dominant or recessive, or partially so, being absent, being sex-linked, being involved in chromosomal aberrations.
allelic g's
different forms of a particular gene usually situated at the same position (locus) in a pair of chromosomes.
gene amplification
see gene duplication (below).
gene bank
the collection of DNA sequences in a given genome. Called also gene library.
barring gene
responsible for the barred pattern on the feathers of Barred Plymouth Rock birds.
gene box
see box (4).
gene clone
see clone.
gene cluster
a group of related genes derived from a common ancestral gene, located closely together on the same chromosome. Called also multigene family.
complementary g's
two independent pairs of nonallelic genes, neither of which is functional without the other.
gene conversion
a non-reciprocal exchange of DNA elements during meiosis which results in a functional rearrangement of chromosomal DNA.
dhfr gene
dihydrofolate reductase gene; an enzyme required to maintain cellular concentrations of H2 folate for nucleotide biosynthesis, and which has been used as a 'selective marker'; cells lacking the enzyme only survive in media containing thymidine, glycine and purines; mutant cells (dhfr) transfected with DNA that is dhfr′ can be selectively grown in medium lacking these elements.
diversity (D) gene
genes located in diversity (D) segment; contribute to the hypervariable region of immunoglobulins.
dominant gene
one that produces an effect (the phenotype) in the organism regardless of the state of the corresponding allele. Examples of traits determined by dominant genes are short hair in cats and black coat color in dogs.
gene duplication
as a result of non-homologous recombination, a chromosome carries two or more copies of a gene.
gene expression
gene frequency
the proportion of the substances or animals in the group which carry a particular gene.
holandric g's
genes located on the Y chromosome and appearing only in male offspring.
immune response (Ir) g's
genes of the major histocompatibility complex (MHC) that govern the immune response to individual immunogens.
jumping gene
see mobile dna.
gene knockout
replacement of a normal gene with a mutant allele, as in gene knockout mice.
lethal gene
one whose presence brings about the death of the organism or permits survival only under certain conditions.
gene library
see gene bank (above).
gene locus
see locus.
mutant gene
one that has undergone a detectable mutation.
non-protein encoding gene
the final products of some genes are RNA molecules rather than proteins.
overlapping g's
when more than one mRNA is transcribed from the same DNA sequence; the mRNAs may be in the same reading frame but of different size or they may be in different reading frames.
gene pool
total of all genes possessed by all members of the population which are capable of reproducing during their lifetime.
gene probe
see probe (2).
recessive gene
one that produces an effect in the organism only when it is transmitted by both parents, i.e. only when the individual is homozygous.
regulator gene, repressor gene
one that synthesizes repressor, a substance which, through interaction with the operator gene, switches off the activity of the structural genes associated with it in the operon.
reporter gene
one that produces products which can be measured and therefore used as an indicator of whether a DNA construct has successfully been transferred.
sex-linked gene
one that is carried on a sex chromosome, especially an X chromosome.
gene splicing
structural gene
nucleotide sequences coding for proteins.
gene therapy
the insertion of functional genes into cells of the host in order to alter its phenotype, usually used to treat an inherited defect.
gene transcription
gene transfer
tumor suppressor g's
a class of genes that encode proteins that normally suppress cell division that when mutated allow cells to continue unrestricted cell division and may result in a tumor.
References in periodicals archive ?
We used paired-end reads to increase the base coverage within expressed genes in a sample and as a result improved SNP detection sensitivity.
similar patients, possibly all having a certain, yet unexplored cancer subtype) rather than explaining sets of differentially expressed genes characteristic for patients of a given class (cancer type) as a whole.
In conclusion, the present study analyzed the differentially expressed genes in urine exfoliated urothelial cells with SSH and cDNA microarray which provided a new and comprehensive expression profile of BTCC.
Extending these results to include all differentially expressed genes, regardless of EPIG pattern, we found that methapyrilene elicits a dose-dependent increase in the number and fold change of differentially expressed genes involved in the ER stress response and/or unfolded protein binding in the liver only, from 16 differentially expressed genes after seven low doses to 42 differentially expressed genes after one high dose up to 64 differentially expressed genes after seven high doses of methapyrilene [Figure 3; Table 1 in Supplemental Material (http://www.
The beauty of SAGE is that it counts close to exactly the number of transcripts of every expressed gene in the entire turkey genome at a particular moment by using digital technology," says Zuelke.
Included in Partek Flow are publicly available statistical algorithms as well as those developed and optimized by Partek such as their Gene Specific Algorithm for the detection of differentially expressed genes, which won the Illumina iDEA Challenge award for most creative algorithm.
The overall trend observed in the large co-expression pattern was also in agreement with the PCA result showing 10 significantly differentially expressed genes.
Hierarchical analysis of differentially expressed genes in blood was also used to discriminate between groups with different genitourinary cancers and between late and early stage bladder cancer.
It identified close to 30,000 of the expressed genes that are thought to make up barrel medic's genome.
Building upon its patented core technologies, AlphaGene has developed an integrated platform that includes gene arraying on biochips thereby identifying differentially expressed genes in disease or other cell states.
In addition, the researchers observed a distinct pattern of selection against mutations within expressed genes compared to non-expressed genes and in promoter regions up to 5 kb upstream of all protein-coding genes.
Four genes were selected from all differently expressed genes for further investigation of their expression.