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( A-C ) ( D - H) ( I M) (N -R ) (S- T ) (U-Z )
I
Antibody variants localized to the variable portion of an immunoglobulin that are recognised by their antigenic determinants. The determinants are composed from the antigen-combining site or CDRs. Every unique antigenic determinant has a specific antibody with its own unique idiotype.
A member of the globulin protein family consisting of two light and two heavy chains linked by disulfide bonds. All antibodies are immunoglobulins.
(Lit. computer mediated). The use of computers to simulate, process, or analyse a biological experiment.
A variation of the DNA/RNA hybridization procedure in which the denatured DNA is in place in the cell and is then challenged with RNA or DNA extracted from another source. (See also fluorescence in situ hybridization).
The physical insertion of DNA into the host cell genome. The process is used by retroviruses where a specific enzyme catalyses the process or can occur at random sites with other DNA (eg. transposons).
The communication of a molecular message from the surface of the cell to the nucleus via the participation of a series of molecules, including receptors, enzymes, proteins, and small-molecules. The end result of the signalling process is the up- or down-regulation of a particular series of genes that may be involved in cell growth, division or differentiation.
Nucleotide sequences found in the structural genes of eukaryotes that are non-coding and interrupt the sequences containing information that codes for polypeptide chains. Intron sequences are spliced out of their RNA transcripts before maturation and protein synthesis. (cf. Exons)
Two different restriction enzymes which recognize and cut DNA at the same recognition site. e.g Sma I and Xma I both recognize and cut the sequence CCCGGG.
Two or more enzymes capable of catalyzing the same reaction but varying in their specificity due to differences in their structures and hence their efficiencies under different environmental conditions.
A series of steps in an algorithm whereby the processing of data is performed repetitively until the result exceeds a particular threshold. Iteration is often used in multiple sequence alignments whereby each set of pairwise alignments are compared with every other, starting with the most similar pairs and progressing to the least similar, until there are no longer any sequence-pairs remaining to be aligned.
J
Term used to describe the excess DNA that is present in the genome beyond that required to encode proteins. A misleading term since these regions are likely to be involved in gene regulation, and other as yet unidentified functions.
K
The constitution (typically number and size) of chromosomes in a cell or individual.
Knockout mice (gene targeting)
Mice which have been engineered to lack a chosen gene. The gene is inactivated in so called embryonic stem cells using the technique of homologous recombination. These cells are then introduced into a early stage embryo (blastocyst) and this is then transplanted into a recipient mouse. The subsequent progeny lack the targeted gene in some cells. This technique is used to determine the function of the chosen gene.
L
Term describing microdevices that allow rapid, microanalytical analysis of DNA or protein in a single, fully integrated system. Typically, these devices are miniature surfaces, made of silicon, glass or plastic, which carry the necessary microdevices (pumps, valves, microfluidic controllers, and detectors) that allow sample separation and analysis. These devices are used in drug discovery, genetic testing and separation science.
A candidate compound identified as the best "hit" (tight binder) after screening of a combinatorial (or other) compound library, that is then taken into further rounds of screening to determine its suitability as a drug.
The process of converting a putative lead compound ("hit") into a therapeutic drug with maximal activity and minimal side affects, typically using a combination of computer-based drug design, medicinal chemistry and pharmacology.
Protein motif which binds DNA in which 4-5 Leucines are found at 7 amino acid intervals. This motif is present typically in transcription factors and other proteins that bind DNA.
In Bioinformatics, a lexicon refers to a pre-defined list of terms that together completely define the contents of a particular database.
(strict.) The component in the grammar which is in bare form a list of words or lexical entries.
A large collection of compounds, peptides, cDNAs or genes which may be screened in order to isolate cognate molecules.
Any small molecule that binds to a protein or receptor; the cognate partner of many cellular proteins, enzymes, and receptors.
The association of genes (or genetic loci) on the same chromosome. Genes that are linked together tend to be transmitted together.
A genetic map of a chromosome or genome delineated by mapping the positions of genes to their chromosomes by their linkage to readily identifiable genetic loci.
The specific position occupied by a gene on a chromosome. At a given locus, any one of the variant forms of a gene may be present. The variants are said to be alleles of that gene.
M
A measure of genetic distance between two linked genes that corresponds to a recombination frequency of 1%.
Any multivariate probability density whose independence diagram is a chain.The variables are ordered, and each variable "depends" only on its neighbors in the sense of being conditionally independent of the others. Markov chains are an integral component of hidden Markov models.
A process within the cell nucleus that results in the reduction of the chromosome number from diploid (two copies of each chromosome) to haploid (a single copy) through two reductive divisions in germ cells.
The denaturation of double-stranded DNA into two single strands by the application of heat. (Denaturation breaks the hydrogen bonds holding the double-stranded DNA together).
The complementary RNA copy of DNA formed from a single-stranded DNA template during transcription that migrates from the nucleus to the cytoplasm where it is processed into a sequence carrying the information to code for a polypeptide domain.
The addition of -CH3 (methyl) groups to a target site. Typically such addition occurs on to the cytosine bases of DNA. (see maternal imprinting).
A 2D array, typically on a glass, filter, or silicon wafer, upon which genes or gene fragments are deposited or synthesized in a predetermined spatial order allowing them to be made available as probes in a high-throughput, parallel manner.
The miniaturization of chemical reactions or pharmacalogical assays into microscopic tubes or vessels in order to greatly increase their throughput, by placing many of them side-by-side in an array.
Compounds that mimic the function of other molecules via their high degree of structural (conformational) similarity, and hence physio-chemical properties.
A point mutation in which one codon (triplet of bases) is changed into another designating a different amino acid.
The nuclear division that results in the replication of the genetic material and its redistribution into each of the daughter cells during cell division.
In bioinformatics, modeling usually refers to molecular modeling, a process whereby the three-dimensional architecture of biological molecules is interpreted (or predicted), visually represented, and manipulated in order to determine their molecular properties. (general) A series of mathematical equations or procedures which simulate a real-life process, given a set of assumptions, boundary parameters, and initial conditions.
A single unit of any biological molecule or macromolecule, such as an amino acid, nucleic acid, polypeptide domain, or protein.
Having one binding site; strictly, an atom with only one free electron available for binding in its highest energy shell.
A conserved element of a protein sequence alignment that usually correlates with a particular function. Motifs are generated from a local multiple protein sequence alignment corresponding to a region whose function or structure is known. It is sufficient that it is conserved, and is hence likely to be predictive of any subsequent occurrence of such a structural/functional region in any other novel protein sequence.
A set of genes derived by duplication of an ancestral gene, followed by independent mutational events resulting in a series of independent genes either clustered together on a chromosome or dispersed throughout the genome.
A Multiple Alignment of k sequences is a rectangular array, consisting of characters taken from the alphabet A, that satisfies the following conditions: There are exactly k rows; ignoring the gap character, row number i is exactly the sequence sI; and each column contains at least one character different from "-". In practice multiple sequence alignments include a cost/weight function, that defines the penalty for the insertion of gaps (the "-" character) and weights identities and conservative substitutions accordingly. Multiple alignment algorithms attempt to create the optimal alignment defined as the one with the lowest cost/weight score.
Approach to high-throughput sequencing that uses several pooled DNA samples run through gels simultaneously and then separated and analyzed.
Any agent that can cause an increase in the rate of mutations in an organism.
An inheritable alteration to the genome that includes genetic (point or single base) changes, or larger scale alterations such as chromosomal deletions or rearrangements.