Bashiyer Alasad
Pronouns: She/her
Research Mentor(s): . Anoop Arunagiri
Co-Presenter:
Research Mentor School/College/Department: Int. Med / Medicine
Presentation Date: April 20
Presentation Type: Oral5
Session: Session 4 – 2:40pm – 3:30 pm
Room: Breakout room 5
Authors: Bashiyer Alasad, Anoop Arunagiri, Leena Haataja, Peter Arvan
Presenter: 6
Abstract
Understanding the critical defects involved in the production of insulin may help discern what makes cells in the diabetic pancreas less efficient and how this ultimately leads to the development of the disease. Growing evidence suggests that increased stress in the endoplasmic reticulum (ER) may be responsible for the loss of pancreatic beta-cell function in the diabetic patient population— specifically in mutant INS gene-induced Diabetes of Youth (MIDY) and Type II Diabetes. The misfolding of proinsulin has been suggested as a potential contributor to the issue. The degree to which proinsulin can misfold has been linked to increased synthesis, altered ER environment, mutational defects, and decreased clearance of misfolded proteins. Thus far, the key covalent interactions, namely the “disulfide linkages†that otherwise primarily stabilize proinsulin structure, have been shown to be involved in the misfolding events, leading to the formation of large proinsulin aggregates in the ER. Using techniques including SDS-PAGE and Western blotting, we are able to evaluate proinsulin levels and folding status in beta cells. The results from these can be related to the source, for example, a diabetic mouse with a known mutational defect. In the present study, we intend to study the effect of familial mutations in the insulin gene that would result in mutant misfolded proinsulin. We will utilize whole-cell extracts and media samples from cultured 293T cells that overexpress wildtype or mutant proinsulin, and biochemically characterize proinsulin folding using the established western blotting methods. This way we will elucidate the effect of the mutation in the proinsulin folding and trafficking. We aim to use this data, as well as the others involving mouse models in near future, to help further examine the molecular mechanisms involved in faulty insulin production and eventual beta-cell failure in the diabetic pancreas.
