New results for ubiquitin published in PNAS
Cataract is the most common form of age-related diseases, and cataract led to 18 million people blind. Precipitation and lens cataract formation and accumulation of harmful proteins related. The ubiquitin proteolytic system is the selective removal of harmful mainly cytoplasmic protein degradation pathway. Ubiquitin has seven lysine, which determines the fate of lysine ubiquitination of substrates, in particular the K6. Sichuan University research team in-depth analysis of the impact of mutations arising K6.
Unique in the eye lens that lens cells last a lifetime, is the ideal model of differentiation or development. The researchers found that, K6 only participated in less than 3% of the ubiquitin ligase, and the lack of impact on the lens protein K6 is not large. In the case of K6 mutations, lens protein profile occurs only about 2% of the change. However, this effect is not apparent mutation has changed the gap junction cells, the core of the lens increases the calcium level and calpain activity, some of the key lens protein is truncated proteins such shear will cause cataracts.
The study showed that ubiquitin K6 mutations interfere with UPS function, and ultimately lead to developmental defects and cataracts. These findings contribute to our understanding of the ubiquitin K6 eye development, it also provides new clues for delaying cataract and other diseases protein precipitation.