at Related Biological Terms

Descriptive of a property of a solution that depends upon the number but not the nature of solute molecules, e.g. osmotic pressure.

A technique for screening bacterial colonies for those that contain a desired polynucleotide sequence. A plate is exposed to a labelled oligonucleotide probe with a sequence complementary to part of the desired sequence which thus labels clones with that sequence. In a variant technique, plaque hybridization, phage vectors are screened for the desired polynucleotide sequence. Related tool: molecular biology tools

(= colour PCR)

Descriptive of procedures or processes that generate a diversity of molecules (e.g. nucleic acid or protein sequences; related chemical structures) that can be screened for a desired property. The collection of molecules is termed a library. (see also small molecule library)

(see repertoire cloning; synthetic peptide combinatorial library (SPCL))

An extended DNA sequence that is sufficiently conserved across a spectrum of species, e.g. all mammals or mouse and human, so as to serve as a marker for comparative genome mapping and assist the search in the genome of a second species of a gene for a trait known from a first species' genome. The most useful CATS will include coding sequences to assist their identification.(see expressed sequence tag; sequence tagged site)Nadeau, J.H. and Sankoff, D. (1997) Nat. genet. 15, 6-7 Recommended reading: next generation sequencing

An application of the comparative mapping of genes and other genetic markers in the genomes of several mammalian species to the localization to a specific chromosomal locus of a gene, in particular one thought to be related to a genetic disease (a candidate disease gene). Because mammalian evolution has resulted in relatively few gene relocations, and since those that have occurred seem to be random, knowledge of linkages of genes in mammalian species may be helpful in locating a gene in another mammal's genome. Eppig, J.T. and Nadeau, J.H. (1995) Curr. Opin. genet. Dev. 5, 709-716 Recommended reading: next generation sequencing

A method for characterization of the microenvironment of an amino acid residue of a protein, e.g. its accessibility to solvent or its pKa; other residues of the same amino acid serve as internal controls. Rates of reaction or ratios of reaction compared with control residues are observed; very limited amounts of reagent and extents of reaction maximize the competition for the reagent between similar groups on the protein and ensure that only unmodified protein reacts with reagent. Related tool: molecular biology tools

A method for identification of a DNA fragment and selection of the defective cell line upon which it confers resistance to a selective pressure, e.g. cells that are hypersensitive to ionizing radiation. Fractions of normal genomic cDNA are screened for ability to confer resistance on cells into which they are introduced. Different lines of defective cells that represent discrete genetic defects may be associated with different cDNA fragments. Learn more about sgRNA.

An oligomer or higher polymer of more than one kind of sugar moiety, or a glycoside formed with a non-sugar compound. (see also glycolipid; glycoprotein; glycoside; heteropolysaccharide; proteoglycan (mucopolysaccharide)) Related tool: molecular biology tools