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  Home >> Molecular Biology Dictionary >> Elastin - Embryogenesis

Elastin
A fibrous protein that is the major constituent of the yellow elastic fibres of connective tissue.

Electro-blotting
The electrophoretic transfer of macromolecules (DNA, RNA or protein) from a gel, in which they have been separated, to a support matrix, such as a nitrocellulose sheet. A transfer usually used in techniques such as Southern and northern blotting

Electroporation
1. An electrical treatment of cells that induces transient pores, through which DNA can enter the cell.

2. The introduction of DNA or RNA into protoplasts or other cells by the momentary disruption of the cell membrane through exposure to an intense electric field
Note: Although the precise mechanism of electroporation is poorly understood, pores are thought to form by the local polarization of the cell membrane when it is exposed to a high electric potential. These openings persist for a variable amount of time, depending upon the temperature at which the cell is treated. Macro-molecules, such as DNA or RNA, enter through these openings either through diffusion or through electrophoretic movement. The membrane openings then re­seal, capturing introduced DNA and preventing escape of the cell contents.
Electrostatic precipitator

A device which uses an electric field to trap particulate pollutants.

Elementary reaction
A reaction in which the rate expression corresponds to the stoichiometric equation.

Elongation factors
Soluble proteins that are required for polypeptide chain elongation
EMBL
European Molecular Biology Laboratories. Maintain the EMBL database, one of the major public sequence databases.

EMBnet
European Molecular Biology Network: http:/ / www.embnet.org was established in 1988, and provides services including local molecular databases and software for molecular biologists in Europe. There are several large outposts of EMBnet, including EXPASY
Embryo
(Gr. en, in + bryein, to swell) An immature organism in the early stages of development. In mammals, this occurs in the first months in the uterus. In  plants, it is the structure that develops in the megagametophyte, as result of the fertilization of an egg cell, or without fertilization. In aseptic cultures, adventitious embryos show polarization, followed by the growth of a shoot from one end and a root from the other end. embryo cloning The creation of identical copies of an embryo by embryo splitting (q.v.) or by nuclear transfer (q.v.) from undifferentiated embryonic cells.

                             

Embryo culture
The culture of embryos on nutrient media.

Embryogenesis
1. (General) Development of an embryo.
2. (In plants) In vitro formation of plants from plant tissues, through a pathway closely resembling normal embryogeny from the zygote; if this development in culture involves somatic cells and not the zygote, it can be indicated by using the term adventitious embryogenesis or somatic embryogenesis. The generation of embryos has two stages: initiation and maturation. Initiation needs a high level of the group of plant hormones called auxins; maturation needs a lower level. Other chemicals have to be at suitable levels. The procedure involves the explanting of a piece of plant tissue and putting it on a high-auxin medium, where the cells grow into a mass of callus. This is then transferred to a maturation medium, where the callus starts to initialize organs, ultimately growing a root and a shoot.
      

 

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