Transformation 2 - Transformation Methods Glossary

callus

A mass of undifferentiated cells used in tissue culture.

chromosome

The genetic structures in cells composed of condensed DNA ,which contain the genetic code for an organism.

chromosome

A genetic structure in a cell composed of condensed DNA, which contains the genetic code for an organism.

DNA

(deoxyribonucleic acid) The molecule that encodes genetic information. DNA is a double-stranded molecule held together by weak bonds between base pairs of nucleotides. It is the fundamental substance of which genes are composed.

electroporation

A method of cell transformation using a pulse of electricity to open small temporary holes in the plant or bacteria cells. The foreign DNA mixed with these cells is able to pass into the cell through these holes.

gene

The fundamental unit of heredity that carries genetic information from one generation to the next. A gene is an ordered sequence of nucleotides located on a particular position on a particular chromosome that encodes a specific functional protein.

gene gun

Also known as microprojectile bombardment and particle acceleration. The method used to transform cells using small gold or tungsten particles which are coated with DNA and literally shot into the cell.

genes

The fundamental unit of heredity that carries genetic information from one generation to the next. A gene is an ordered sequence of nucleotides located on a particular position on a particular chromosome that encodes a specific functional protein.

marker

An easy to detect trait controlled by a known gene. Markers, such as antibiotic or herbicide resistance, are often used to determine if an organism is transgenic.

marker gene

A gene controlling an easily detectable trait used to select transgenic cells or plants from non-transgenic ones, (i.e., herbicide and antibiotic resistance).

microfibers

A method used to transform tissue culture cells using tiny fibers coated with DNA. These fibers are combined in solution with the cells and shaken vigorously causing the fibers to stab the plant cells delivering the DNA to them.

nucleus

The part of the plant or animal cell that contains the chromosomes.

plasmid

A small circular piece of DNA from bacteria that often contains antibiotic resistance genes. Some types have the capability to be replicated in the bacteria and integrate itself into the genome of a plant.

plasmids

Small circular pieces of DNA found in bacteria. Scientists use these to put cloned pieces of DNA into.

replicate

The copying of a DNA molecule in a cell.

selection media

Agarose media containing the substance for which the selectable marker gene encodes resistance. When tissue culture cells are place on this media, cells that have not been transformed and do not contain the gene conferring resistance to the substance will die leaving only those cells that are transgenic.

Ti plasmid

A circle of DNA found in Agrobacterium tumifaciens that encodes genes for moving the plasmid into a plant cell and inserting a portion of the plasmid into the plant chromosome.

tissue culture

Plant cells are grown in culture which allows them to be manipulated and then induced to develop into whole plants.

transformation

A process by which extra genetic material is inserted into the cells of an individual.

transgene

A gene that has been genetically altered. They are usually used to transform organisms.

transgenic

An organism that has a new genetically engineered DNA sequence found in every one of its cells. Genetically engineered organisms are transgenic. These two terms are used interchangeably.

transgenic plant

A plant that has a new genetically engineered DNA sequence present in every one of its cells. Genetically engineered plants are transgenic plants. These two terms are used interchangeably.