The world's first wiki where authorship really matters (Nature Genetics, 2008). Due credit and reputation for authors. Imagine a global collaborative knowledge base for original thoughts. Search thousands of articles and collaborate with scientists around the globe.

wikigene or wiki gene protein drug chemical gene disease author authorship tracking collaborative publishing evolutionary knowledge reputation system wiki2.0 global collaboration genes proteins drugs chemicals diseases compound
Hoffmann, R. A wiki for the life sciences where authorship matters. Nature Genetics (2008)

Proteolytic activation of sterol regulatory element-binding protein induced by cellular stress through depletion of Insig-1.

Insig-1 and Insig-2 are closely related proteins of the endoplasmic reticulum (ER) that block proteolytic activation of sterol regulatory element-binding proteins (SREBPs), membrane-bound transcription factors that activate synthesis of cholesterol and fatty acids in animal cells. When cellular cholesterol levels are high, Insig proteins bind to SREBP cleavage-activating protein, retaining it in the ER and preventing it from escorting SREBPs to the site of proteolytic activation in the Golgi complex. Here we report that hypotonic stress reverses the sterol-mediated inhibition of SREBP proteolytic activation by reducing the level of Insig-1 but not Insig-2. The reduction of Insig-1, a protein with a rapid turnover rate, results from a general inhibition of protein synthesis mediated by hypotonic stress. Insig-2 is not affected by hypotonic stress because of its slower turnover rate. Inhibition of protein synthesis by hypotonic shock has not been reported previously. Thapsigargin, an activator of the ER stress response, also inhibits protein synthesis and activates proteolysis of SREBP. Such activation also correlates with the disappearance of Insig-1. The current study demonstrates that animal cells, in response to either hypotonic shock or ER stress, can bypass the cholesterol inhibition of SREBP processing, an effect that is attributable to the rapid turnover of Insig-1.[1]


WikiGenes - Universities