Biochemical and Biophysical Research Communications
Measuring the balance between insulin synthesis and insulin release
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2017, Free Radical Biology and MedicineCitation Excerpt :In addition to palmitate-induced ER-stress and peroxisomal H2O2 generation, an excessive proinsulin biosynthesis, which occurs during β-cell compensation, has been implicated in the induction of chronic unresolved ER stress by overwhelming the processing and folding capacity of the ER [20–23]. Insulin as the major biosynthetic product of the β-cell accounting for around 50% of the total protein production [24–26], must be oxidatively folded to maintain its structural stability and biological activity. Oxidative protein folding takes place in the ER lumen and is accomplished by ER-resident protein disulfides (PDIs) and ER oxidoreductin members (ERO1α and ERO1β), generating equimolar H2O2 as a by-product [27,28].
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