gene Related Biological Terms

An imprecise term that sometimes refers to the nature of the amino acid residues of a protein which determine its secondary and tertiary structure, and sometimes to the features of a tRNA molecule that make it recognizable by one amino acid synthetase but not by others.

DNA that functions to propagate itself to the detriment of other DNA sequences of the genome; e.g. a DNA that encodes an endonuclease that specifically cleaves an allele that does not contain the nuclease gene, and allows conversion of the heterozygous cell into a homozygous cell that contains the selfish DNA, or a lethal or detrimental gene that persists during the evolution of an organism, perhaps due to its close linkage to essential genes. Grivell, L.A. (1992) Curr. Biol. 2, 450-452; Bull, J.J., Molineux, I.J. and Werren, J.H. (1992) Science 256, 65

A technique to alter deliberately a structural gene to insert a desired point mutation. A synthetic polynucleotide that contains the genetic alteration is used as an imperfectly fitting primer in replication and the completed (-)-strand incorporates the mutation.

(= site-directed mutagenesis)

(see gene therapy)

A gene whose coding sequence is interrupted by introns.

A polynucleotide that in one form, c-src, is a normal cellular gene, and in a similar form, v-src, is an oncogene of avian sarcoma virus.

(see oncogene)

The process of generation of heat by the uncoupling of electron transport, especially in brown adipose tissue.

A theory of the origin of life, particularly of how prebiotic structures utilized environmental energy to drive synthetic processes. Basing itself on the current belief that the most primitive organisms are the thermophilic micro-organisms, the theory holds that prebiotic synthesis was driven by temperature variation, perhaps owing to convection currents near undersea thermal vents. A population of proteins is assumed, having been formed by processes postulated by other theories of the origin of life. Among these proteins was the original enzyme, an ATP synthase, which underwent a reversible temperature-dependent folding/unfolding: cycles of temperature variation drove the synthesis of ATP, or other phosphoanhydride, by binding substrates at a lower temperature and facilitating synthesis of an anhydride bond on the protein surface; as the protein unfolded at the higher temperature, it dissociated the ATP (protein-associated thermosynthesis). When the components of membranes became available, the synthase activity was incorporated into them and formed primitive chemosmotic vesicles (membrane-associated thermosynthesis). Variations in incident light e.g. under the waves of shallow water, might have energized primitive photosynthetic vesicles.Muller, W.J. (1996) Essays Biochem. 31, 103-119