Transgenic Mice: Target Gene Overexpression

Strains obtained by experimentally introducing exogenous genes into early embryos and integrating them into the genome for stable inheritance of target traits.

Random Insertion

  • Random insertion transgenesis
  • Transposon-mediated site-selective transgenesis

Site-specific Insertion

  • ES/Cas9-mediated knock-in transgenesis
  • Conditional overexpression (Cre-LoxP)

Random Transgenesis Workflow

1. Plasmid Construction
2. Microinjection
3. Embryo Transfer
4. Obtain F0

Key Advantages

  • Simple construction & low technical difficulty
  • Short cycle (F0 obtained in 3 months)
  • Supports large fragments (>100kb)

Technical Considerations

  • Uncertain expression intensity/patterns
  • Requires line establishment for validation
  • Needs 2-3 lines to confirm phenotype

Site-Specific Transgenesis

Insertion of DNA at a 'Safe Harbor' site to ensure stable expression without disrupting endogenous genes.

Random Transgenesis

  • Random insertion site & copy number
  • Risk of disrupting endogenous genes
  • Significant line screening effort required
VS

Targeted Transgenesis

  • Unique model with precise localization
  • No impact on endogenous gene expression
  • High genetic stability / no screening needed

Direct & Conditional Overexpression

Direct Overexpression (Safe Harbors)

Target fragments are knocked-in at validated locations:

Rosa26 (Chr 6)
H11 (Chr 11)
Col1a1 (Chr 6)
Safe Harbor Sites

Conditional Overexpression

Utilizing the Cre-LoxP system for inducible and tissue-specific regulation of the target gene.

Conditional Construct