Transgenic rats are animal models which have foreign DNA incorporated into the rat genome and are used to research a wide range of gene functions and human diseases.

In this article, we review the basic information on transgenic rat models, research application examples, and how they can be developed.

 

What are Transgenic Rats Used For?

Transgenic rats are the first choice of pharmacology research animals, which are widely used in the study of cardiovasology, oncology, diabetes, breast cancer, and neurological diseases. Transgenic rats can simulate human diseases which can help researchers discover pathogenic genes of the diseases and gain a better understanding of the relationship between genes and their environment that may ultimately affect human health. Transgenic rats have been widely used in testing the efficacy and safety of drugs, which has accelerated the drug screening efficiency and accuracy.

 

How Are Transgenic Rats Generated?

Pronuclear injection (PNI) is the most common method used to generate transgenic rats. Pronuclear injection refers to injecting exogenous DNA into the nucleus of a fertilized egg by microinjection, integrating DNA into the genome of fertilized eggs in rats, which passes on the transgene to offspring. Cyagen’s PiggyBac transgenic pronuclear injection can improve the positive rate of gene expression in transgenic offspring by more than twice that of conventional plasmid DNA microinjection! PiggyBac transgenic rats provide high and consistent expression of a transgene, improving model data reliability for research of human diseases and drug treatments.

 

How Does the PiggyBac Transposon System Work?

The PiggyBac (PB) transposon system utilizes a unique "cut and paste" mechanism to transfer DNA fragments between vectors and chromosomes, effectively mediating the integration of foreign DNA fragments into the genome. Upon transposition, transposases efficiently recognize specific transposon sequences (inverted terminal repeats, ITRs), binding to the transposon ends to form a transient hairpin structure that disengages after “cut” and “pastes” to the TTAA site of the genome. Our experimental data indicates that the PiggyBac system yields more than 2 times the positive gene expression rate in offspring, as compared to conventional plasmid DNA microinjection.

 

Our proprietary PiggyBac transgenic method has the following advantages over other transgenic approaches:

  • Single-copy integration: Avoids potential gene silencing from multiple copies per integration site
  • Defined region of integration: No loss of transgene sequence (TTAA, transcription unit)
  • Reliability: More consistent expression pattern compared to plasmid-based transgenics
  • Economical: Cost and turnaround time comparable to plasmid-based transgenics

>> Learn more about PiggyBac transgenic rat models

 

Transgenic Services

Cyagen provides comprehensive model generation services for all your transgenic mouse, mouse embryo, and rat model needs. Contact us to perform your entire project - from initial strategy design and DNA vector construction, all the way through breeding – we deliver research-ready transgenic rodent models for guaranteed results.

  Regular Transgenic PiggyBac Transgenic
Integration Random, multicopy integration Random, single copy per integration site
Vector construction Transgenic plasmid or BAC Transgenic plasmid or BAC
Expression pattern Variable expression in founders More consistent expression in founders
Endogenous effects Can disrupt endogenous gene expression Less likely to disrupt endogenous gene expression
Zygosity Hemizygous Hemizygous