Creation of a eukaryotic multiplexed site-specific inversion system and its application for metabolic engineering.

The site-specific recombination system is a versatile tool in genome engineering, enabling controlled DNA inversion or deletion at specific sites to generate genetic diversity. The multiplexed inversion system, which preferentially facilitates inversion at reverse-oriented sites rather than deletion at same-oriented sites, has not been found in eukaryotes. Here, we establish a multiplexed site-specific inversion system, Rci51-5/multi-sfxa101, in yeast.

A DNA Inversion System in Eukaryotes Established via Laboratory Evolution.

DNA inversion is a type of site-specific recombination system that plays an important role in the generation of genetic diversity and phenotypic adaptation by programmed rearrangements in bacteria. However, no such inversion system exhibiting a strong directionality bias has been identified or developed in eukaryotes yet. Here, using directed evolution of Rci recombinase, a tyrosine recombinase from a bacterial DNA inversion system, we identified a mutant Rci8 with a ratio of inversion/deletion up to ∼4320 in yeast.

[Influence of tert-butylhydroquinone on the islets function and expression of HO-1 and VEGF in retina of type 2 diabetic rats].

Objective: To observe the effect of tert-butylhydroquinone (tBHQ) on the islets function and expression of HO-1 and VEGF in retina of type 2 diabetic rats.

Methods: Experimental study. Forty healthy male Sprague-Dawley rats with 6 weeks old were given high-fat and high-sugar diet for 4 weeks and then intraperitoneal injection with streptozotocin(STZ) 30mg/kg to induce diabetic model.