Table 1.

Glossary of common terms in genetic engineering.

AblationElimination of undesired tissues by causing cell death
AgrobacteriumA bacterium that transfers DNA into plant cells; used for genetic engineering of plants
Antisense-suppressionA method for inhibiting a gene’s expression by introducing a reverse copy of the gene
cDNASynthesized from a mRNA in vitro; corresponds to the expressed form of a gene (without introns)
Constitutive gene expressionA gene expressed in virtually all cells at all times
CytotoxinA protein that, when expressed in specific cells, causes cell death
Dominant negative mutation (DNWI)A mutation in a gene that results in a nonfunctional protein that also inhibits the activity of the wild-type protein
Homeotic geneA gene that when rendered nonfunctional causes an organ to develop in the wrong place (e.g., petals develop where stamens normally form)
InflorescenceStructure on which flowers occur (e.g., a catkin)
IntronDNA sequence that interrupts the protein-coding sequence of a gene; present in nearly all genes in higher organisms
Gene expressionThe process by which genetic information is read and turned into mRNA and then protein
Gene silencingInhibition of a gene’s expression
GenomeAll the DNA sequence contained in an organism
MeristemGroups of undifferentiated cells from which organ-forming cells arise (e.g., within apical buds and cambium)
Messenger RNA(mRNA)Complimentary to one strand of DNA, after introns are removed; serves as the template for synthesizing a protein
PromoterA regulatory DNA sequence located in front of the coding portion of a gene; it controls when, where, and to what level a gene is expressed
Sense-suppressionA method for inhibiting a gene’s expression by introducing a duplicate or slightly mutated version of the gene
Sequence conservationThe sequence of a particular gene is similar across diverse species; sequence of a gene isolated in one species can be used to easily isolate the corresponding gene (homolog) from a different species
TranscriptionThe synthesis of RNA from DNA
Transcription factorA protein that regulates the expression of genes by interacting with their promoters
TransgeneA gene introduced into the chromo-some of a plant via a nonsexual process
TranslationThe synthesis of a protein from a mRNA template
Wild-type geneA “normal” gene that encodes a fully functional protein