Epitope Tagging

Category: Education

Presentation Description

Epitope Tagging


Presentation Transcript


E pitope Tagging Geetika Mehta


EPITOPE TAGGING An  epitope , also known as  antigenic determinant , is the part of an antigen that is recognized by the immune system, specifically by antibodies, B cells, or T cells. For example, the epitope is the specific piece of the antigen that an antibody binds to. The part of an antibody that binds to the epitope is called a paratope. A single large molecule such as a protein may have many epitopes .


EPITOPE TAGGING Epitope tagging makes it possible to gather information about proteins that would otherwise be too difficult to purify or too similar to other proteins to be distinguished in vivo.


APPICATIONS IN CROP IMPROVEMENT Epitope tagging is a recombinant DNA method by which a protein encoded by a cloned gene is made immuno-reactive to a known antibody. Applications of epitope tagging: Major areas of application include monitoring protein expression, localizing proteins at the cellular and subcellular levels, and protein purification, analysis of protein topology, dynamics and interactions. Recently the method has also found use in transgenic and gene therapy studies and in the emerging fields of functional genomics and proteomics.

Example: Rice:

Example: Rice Furuichi T (2010) studied the expression of epitope -tagged proteins in plants. Although immunoelectron microscopy is a powerful tool for visualizing the subcellular localization of target proteins, it is difficult to obtain and purify the specific antibodies required for this method. Instead of raising antibodies against individual target proteins, the use of transgenic plants expressing epitope -tagged proteins and commercially available antibodies simplifies the subcellular localization of target proteins. An improved method has been described for producing transgenic plants that express epitope -tagged proteins and can be used for immunoelectron microscopic analysis.


CONCLUSIONS Four important methods of gene tagging are: Marker based gene tagging, T-DNA tagging, Transposon tagging, and epitope tagging Marker based gene tagging is the most common among all and has been successfully used in a number of crop plants. T-DNA tagging is used by random insertion of T-DNA along with a target gene. T-DNA acts as a marker for the trait ( colour assay or through tumor induction trait) Transposon tagging and epidope tagging is fairly recent technique. Transposons insertion leads to gene inactivation and thus can be used as a tagging element in genomics. Epitope tagging is generally used to study the expression of a protein.

authorStream Live Help