A myc tag is a polypeptide
protein tag
Protein tags are peptide sequences genetically grafted onto a recombinant protein. Tags are attached to proteins for various purposes. They can be added to either end of the target protein, so they are either C-terminus or N-terminus specific or a ...
derived from the
c-myc
''Myc'' is a family of regulator genes and proto-oncogenes that code for transcription factors. The ''Myc'' family consists of three related human genes: ''c-myc'' (MYC), ''l-myc'' (MYCL), and ''n-myc'' (MYCN). ''c-myc'' (also sometimes referre ...
gene product that can be added to a protein using
recombinant DNA
Recombinant DNA (rDNA) molecules are DNA molecules formed by laboratory methods of genetic recombination (such as molecular cloning) that bring together genetic material from multiple sources, creating sequences that would not otherwise be foun ...
technology. It can be used for
affinity chromatography
Affinity chromatography is a method of separating a biomolecule from a mixture, based on a highly specific macromolecular binding interaction between the biomolecule and another substance. The specific type of binding interaction depends on the ...
, then used to separate recombinant, overexpressed protein from wild type protein expressed by the host organism. It can also be used in the isolation of protein complexes with multiple subunits.
A myc tag can be used in many different assays that require recognition by an
antibody
An antibody (Ab), also known as an immunoglobulin (Ig), is a large, Y-shaped protein used by the immune system to identify and neutralize foreign objects such as pathogenic bacteria and viruses. The antibody recognizes a unique molecule of the ...
and was originally identified in 1985. If there is no antibody against the studied protein, adding a myc-tag allows one to follow the protein with an antibody against the Myc epitope. Examples are cellulite localization studies by immunofluorescence or detection by
Western blotting
The western blot (sometimes called the protein immunoblot), or western blotting, is a widely used analytical technique in molecular biology and immunogenetics to detect specific proteins in a sample of tissue homogenate or extract. Besides detecti ...
.
The peptide sequence of the myc-tag is (in 1- and 3-letter codes, respectively): EQKLISEEDL and Glu-Gln-Lys-Leu-Ile-Ser-Glu-Glu-Asp-Leu. The tag is approximately 1202
Daltons in atomic mass and has 10 amino acids.
It can be fused to the
C-terminus
The C-terminus (also known as the carboxyl-terminus, carboxy-terminus, C-terminal tail, C-terminal end, or COOH-terminus) is the end of an amino acid chain (protein or polypeptide), terminated by a free carboxyl group (-COOH). When the protein is ...
and the
N-terminus
The N-terminus (also known as the amino-terminus, NH2-terminus, N-terminal end or amine-terminus) is the start of a protein or polypeptide, referring to the free amine group (-NH2) located at the end of a polypeptide. Within a peptide, the ami ...
of a protein. It is advisable not to fuse the myc-tag directly behind the signal peptide of a secretory protein, since it can interfere with translocation into the
secretory pathway 440px
Secretion is the movement of material from one point to another, such as a secreted chemical substance from a cell or gland. In contrast, excretion is the removal of certain substances or waste products from a cell or organism. The classical ...
.
A monoclonal antibody against the myc
epitope
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. The epitope is the specific piece of the antigen to which an antibody binds. The p ...
, named 9E10, is available from the non-commercial
Developmental Studies Hybridoma Bank.
See also
*
Protein tag
Protein tags are peptide sequences genetically grafted onto a recombinant protein. Tags are attached to proteins for various purposes. They can be added to either end of the target protein, so they are either C-terminus or N-terminus specific or a ...
**
Polyhistidine-tag
A polyhistidine-tag is an amino acid motif in proteins that typically consists of at least six histidine (''His'') residues, often at the N- or C-terminus of the protein. It is also known as hexa histidine-tag, 6xHis-tag, His6 tag, by the US trad ...
**
SpyTag
**
Flag-tag FLAG-tag, or FLAG octapeptide, or FLAG epitope, is a peptide protein tag that can be added to a protein using recombinant DNA technology, having the sequence DYKDDDDK (where D= aspartic acid, Y=tyrosine, and K= lysine). It is one of the most specifi ...
References
{{Protein tag
Biochemistry
Peptide sequences