HA-tag

From Wikipedia, the free encyclopedia
Jump to navigation Jump to search

Template:Short description

File:HA tag.png
12CA5 Fv-clasp fragment (green, cyan) with its antigen peptide, YPYDVPDYA (magenta), which is used as HA tag. Image created with PyMOL from Template:PDB.

The HA-tag is a protein tag derived from the human influenza hemagglutinin (HA) protein, which allows the virus to target and enter host cells. An HA-tag is composed of a peptide derived from the HA-molecule corresponding to amino acids 98-106, which can be recognized and selectively bound by commercially available antibodies. This makes HA a powerful tool in molecular biology, commonly included in expression vectors and in the production of recombinant proteins. [1] Like other epitope tags, HA-tag is small and generally does not alter the traits of proteins it is attached to.[2] As a result HA-tags are often used to identify protein-protein interactions or to detect protein expression, using Co-Immunoprecipitation or Western blot respectively.[3][4]

The HA-tag is not suitable for detection or purification of proteins from apoptotic cells since it is cleaved by Caspase-3 and / or Caspase-7 after its sequence DVPD, causing it to lose its immunoreactivity.[5] Labeling of endogenous proteins with HA-tag using CRISPR was recently accomplished in-vivo in differentiated neurons.[6]

Sequence

The DNA sequences for the HA-tag include: 5'-TAC-CCA-TAC-GAT-GTT-CCA-GAT-TAC-GCT-3' or 5'-TAT-CCA-TAT-GAT-GTT-CCA-GAT-TAT-GCT-3'. The resulting amino acid sequence is YPYDVPDYA (Tyr-Pro-Tyr-Asp-Val-Pro-Asp-Tyr-Ala).[7]

See also

Script error: No such module "Portal".

References

<templatestyles src="Reflist/styles.css" />

  1. Script error: No such module "Citation/CS1".
  2. Script error: No such module "Citation/CS1".
  3. Script error: No such module "citation/CS1".
  4. Script error: No such module "citation/CS1".
  5. Script error: No such module "Citation/CS1".
  6. Script error: No such module "Citation/CS1".
  7. Script error: No such module "citation/CS1".

Script error: No such module "Check for unknown parameters".

Further reading

<templatestyles src="Refbegin/styles.css" />

  • Script error: No such module "Citation/CS1".

Template:Protein tag Script error: No such module "Navbox".