title: A microchip platform for structural oncology applications.
abstract: Recent advances in the development of functional materials offer new tools to dissect human health and disease mechanisms. The use of tunable surfaces is especially appealing as substrates can be tailored to fit applications involving specific cell types or tissues. Here we use tunable materials to facilitate the three-dimensional (3D) analysis of BRCA1 gene regulatory complexes derived from human cancer cells. We employed a recently developed microchip platform to isolate BRCA1 protein assemblies natively formed in breast cancer cells with and without BRCA1 mutations. The captured assemblies proved amenable to cryo-electron microscopy (EM) imaging and downstream computational analysis. Resulting 3D structures reveal the manner in which wild-type BRCA1 engages the RNA polymerase II (RNAP II) core complex that contained K63-linked ubiquitin moieties-a putative signal for DNA repair. Importantly, we also determined that molecular assemblies harboring theBRCA15382insCmutation exhibited altered protein interactions and ubiquitination patterns compared to wild-type complexes. Overall, our analyses proved optimal for developing new structural oncology applications involving patient-derived cancer cells, while expanding our knowledge of BRCA1's role in gene regulatory events.
authors: Virginia Tech Carilion Research Institute, Roanoke, VA, USA ; School of Biomedical Engineering and Science, Virginia Tech, Blacksburg, VA, USA.
authors: Carly E
authors: CE
authors: Winton
authors: Virginia Tech Carilion Research Institute, Roanoke, VA, USA.
authors: Brian L
authors: BL
authors: Gilmore
authors: Virginia Tech Carilion Research Institute, Roanoke, VA, USA ; Virginia Tech Carilion School of Medicine, Roanoke, VA, USA.
authors: Andrew C
authors: AC
authors: Demmert
authors: Virginia Tech Carilion Research Institute, Roanoke, VA, USA.
authors: Vasilea
authors: V
authors: Karageorge
authors: Virginia Tech Carilion Research Institute, Roanoke, VA, USA ; Virginia Tech Carilion School of Medicine, Roanoke, VA, USA.
authors: Zhi
authors: Z
authors: Sheng
authors: Virginia Tech Carilion Research Institute, Roanoke, VA, USA ; School of Biomedical Engineering and Science, Virginia Tech, Blacksburg, VA, USA ; Virginia Tech Carilion School of Medicine, Roanoke, VA, USA ; Department of Biological Sciences, Virginia Tech, Blacksburg, VA, USA.
authors: Deborah F
authors: DF
authors: Kelly