HA Tag Knockin Mice

HA tag is inserted at the N-terminus (after start codon) or C-terminus (before stop codon) of the target gene, creating a fusion protein. The HA tag sequence (YPYDVPDYA) is inserted in-frame. N-terminal tagging is common for immunoprecipitation; C-terminal tagging preserves signal sequences.

HA tag provides excellent antibody availability with high-affinity anti-HA antibodies suitable for immunoprecipitation, Western blot, immunohistochemistry, and flow cytometry. HA tag is small (9 amino acids), minimizing potential effects on protein function. It may be preferred when FLAG antibodies show background in specific tissues.

Yes. Conditional HA tag knockins can use LoxP-flanked stop cassettes that prevent tag expression until Cre-mediated recombination removes the stop. This enables tissue specific or temporal control of tagged protein expression when combined with appropriate Cre driver lines (tissue specific Cre or inducible CreER).

Pre-germline characterization includes Southern blot analysis to confirm correct targeting and sequence verification to ensure HA tag sequence integrity. Post-germline validation includes Western blot (anti-HA antibody), immunoprecipitation, or immunohistochemistry to confirm tag expression and proper protein localization.