1 / 7

Aleksandar Jeremic Department of Biological Sciences The George Washington University

Molecular Mechanism of Insulin and Amylin Release in the b -cell and Etiology of Type II Diabetes Mellitus. Aleksandar Jeremic Department of Biological Sciences The George Washington University Phone: (202) 994-7899 Email: jerema@gwu.edu http://www.gwu.edu/%7Eclade/faculty/jeremic /.

mala
Download Presentation

Aleksandar Jeremic Department of Biological Sciences The George Washington University

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Molecular Mechanism of Insulin and Amylin Release in the b-cell and Etiology of Type II Diabetes Mellitus Aleksandar Jeremic Department of Biological Sciences The George Washington University Phone: (202) 994-7899 Email: jerema@gwu.edu http://www.gwu.edu/%7Eclade/faculty/jeremic/

  2. 2D / 3D AFM image of amylin fibril growth insulin amylin Overall Goal: To dissect the “nanomechaniscs” of the insulin and amylin release in the b-cell and etiology of TTDM

  3. Research Aims Aim 1.Unraveling machinery regulating insulin and amylin release in b-cells: A. Role of intracellular water channels and heterotrimeric G-proteins B. Role of GTP-ase dynamin and actin Aim 2.Molecular mechanism of amylin –derived islet amyloidosis: A. Role of chaperones B. Role of metal (Zn)-peptide complexes

  4. Aim 1. Nanoscale Imaging of Hormone Secretion and Membrane Dynamics in the b-cell Approach: -Combined AFM and Confocal imaging Phogrin NPY Secretory vesicle NPY-RFP (cargo) Phogrin-GFP (membrane)

  5. Role of intracellular water channels and heterotrimeric G-proteins in regulation of insulin release Role of dynamin and actin in the fusion pore dynamics and vesicle recycling in the b-cell Approach: -AFM, Confocal, ELISA - RNA interference - Inhibitors (cytoch. D) Approach: -AFM, Confocal Microscopy, ELISA -Blockers (Hg; Ab) -AQPs (RNA interference)

  6. Aim 2. Molecular mechanism of islet amyloidosis 18 23 25 29 hAmylin: KCNTATCATQRLANFLVHSSNNFGAILSSTNVGSNTY rAmylin: KCNTATCATQRLANFLVRSSNNLGPVLPPTNVGSNTY insulin b-cell amylin (MIN-6) amyloid fibrils Approach: -Dynamics of amyloid fibril assembly (time-lapse AFM) -Dysfunction of insulin release (TIRF and ELISA) -Cell integrity (Ca2+ imaging, Caspases activation) -Peptide conformation transitions (CD and Raman Spectroscopy) -Protein-Lipid interactions (AFM-Force Imaging; microcalorimetry)

  7. Role of chaperones in amylin processing and fibrilogenesis Role of metal-peptide complexes in islet amyloid fibril formation Zn 7B2 Chaperone insulin amylin PC2 pre-pro-amylin amylin • Approach: • - RNA interference • Over expression of its dominant • negative form • Approach: • - AFM, CD, ITC • Single aa substitution: • 1. His18 (Zn-peptide complex) • 2. Phe23 (aromatic interactions) • 3. Pro25-29 (secondary structure)

More Related