For more than 15 years, Clontech’s Tet-On and Tet-Off brands have been the highest-performing and most-cited mammalian expression systems. During this time, a series of improvements to the system have resulted in three distinct generations of the technology. This page lists the remaining 1st generation Tet-On and Tet-Off vectors. To learn about Tet-On 3G, the highest-performing Tet-On inducible expression system, visit the Tet-On 3G page.
1st Generation: Tet-On and Tet-Off
The original systems described by the laboratories of Hermann Bujard, Manfred Gossen and Wolfgang Hillen and launched by Clontech in 1996. Their performance has been surpassed by two subsequent generations.
2nd Generation: Tet-On Advanced and Tet-Off Advanced
Compared to the original Tet-On and Tet-Off Systems, our Tet-Advanced Systems have been optimized for improved expression in mammalian cells by utilizing human codon preferences and removing cryptic splice sites from the mRNA sequence of the transactivator. These enhancements lead to higher and more stable expression levels, while the three minimal VP16 transcription activation domains minimize off-target effects and reduce toxicity. The PTight promoter contains a modified TRE that both reduces basal expression and promotes tight binding to the Tet-Advanced transactivator proteins during induction to permit specific and high-level transcription of your downstream gene.
3rd Generation—Tet-On 3G
Tet-On 3G is the most advanced inducible expression system for mammalian cells. The transactivator is similar to Tet-On Advanced but additional mutations leads to further sensitivity to doxycycline. Moreover, sequence optimization within the PTRE3G promoter further reduces basal expression up to 15 fold compared to 2nd generation systems. To read more about Tet-On 3G, please visit the Tet-On 3G product page.
