cells Cells (e.g., bacteria, plant, or yeast) that can take up DNA and become genetically transformed.

Control elements

DNA sequences in genes that interact with regulatory proteins (such as transcription factors) to determine the rate and timing of expression of the genes, as well as the beginning and end of the transcript.

CpG methylation

A heritable chemical modification of DNA (replacement of cytosine by 5-methyl cytosine) that, when present in a control region, usually suppresses expression of the corresponding gene.


Mating between members of different populations (lines, breeds, races, or species).

Cytoplasmic inheritance

Hereditary transmission dependent on cytoplasmic genes (genes located on DNA outside the nucleus).

Ectopic gene expression

Expression of a (trans) gene in a tissue or developmental stage when such expression is not expected.


Introduction of DNA into a cell mediated by a brief pulse of electricity.


Derived from within; from the same cell type or organism.

Epithelial cell

The tissue that forms the superficial layer of skin and some organs. It also forms the inner lining of blood vessels, ducts, body cavities, and the interior of the respiratory, digestive, urinary, and reproductive systems.


The ability to survive to reproductive age and produce viable offspring. Fitness also describes the frequency distribution of reproductive success for a population of mature adults.


Toxic compounds found primarily in species of the Apiaceae and Rutaceae plant families. They come in a variety of related chemical structures and have adverse effects on a wide variety of organisms, ranging from bacteria to mammals.

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