Protein quality control, protein-protein interactions, ubiquitination, chaperoned refolding, membrane protein structure/function
A diverse range of diseases, including cancers, cystic fibrosis and degenerative muscle diseases are the result of altered cell surface residency or aberrant folding of membrane proteins due to defects in protein quality control pathways. Our research seeks to understand the molecular interactions and mechanisms that govern membrane protein quality control at the endoplasmic reticulum (ER). My laboratory utilizes nuclear magnetic resonance (NMR), X-ray crystallography, and biophysical and biochemical approaches to study ER quality control (ERQC) and ER-associated degradation (ERAD) of membrane proteins.
Our goals are: (1) to characterize the molecular basis of recognition and ubiquitination of membrane protein ERAD substrates by ER embedded substrate recognition complexes and the cytoplasmic ubiquitination machinery, and (2) to elucidate the regulatory role of ER lumenal chaperones in ERQC. The rationale is that these studies will (a) clarify the interactions and molecular signals within ER-embedded chaperoned-ubiquitination complexes that are perturbed in various pathologies, (b) define the mechanisms by which ER lumenal chaperones target proteins for refolding or degradation and (c) identify structural elements or recognition sequences within ERQC/ERAD enzymes or substrates that may be targeted for therapeutic modulation.
Page, R.C., Pruneda, J., Amick, J., Klevit, R.E. and †Misra, S., Structural insights into the conformation and oligomerization of E2~ubiquitin conjugates. Biochemistry, 51(20), 4175-4187 (2012). PubMed ID 22551455.
Page, R.C., Xu, Z., Amick, J., Nix, J.C. and †Misra, S., Crystallization and preliminary X-ray crystallographic analysis of the Bag2 amino-terminal domain from Mus musculus. Acta Crystallographica Section F, F68(6), 647-651 (2012). PubMed ID 22684061.
Klenotic, P.A., Page, R.C., Misra, S. and †Silverstein, R.L. Expression, purification and structural characterization of functionally replete Thrombospondin-1 type 1 repeats in a bacterial expression system. Protein Expression and Purification, 80(2), 253-259 (2011). PubMed ID 21821127.
Bulek, K., Liu, C., Swaidani, S., Wang, L., Page, R.C., Gulen, M.F., Herjan, T., Abbadi, A., Qian, W., Sun, D., Lauer, M., Hascal, V., Misra, S., Chance, M., Aronica, M., Hamilton, T. and Li, X. IKKi is required for interleukin 17-dependent signaling associated with neutrophilia and pulmonary inflammation. Nature Immunology, 12(9), 844-852 (2011). PubMed ID 21822257.
Page, R.C., Clark, J.G. and †Misra, S. Structure of filamin A immunoglobulin-like repeat 10 from Homo sapiens. Acta Crystallographica Section F, F67(8), 871-876 (2011). PubMed ID 21821884.
Smith, L., Page, R.C., Xu, Z., Kohli, E., Litman, P., Nix, J.C., Icthychanda, S.S., Liu, J., Qin, J., Misra, S. and Liedtke, C., Biochemical basis of the interaction between cystic fibrosis transmembrane conductance regulator (CFTR) and immunoglobulin-like repeats of Filamin. Journal of Biological Chemistry, 285(22), 17166-17176 (2010). PubMed ID 20351101.
Yang, J., Yan-Qing, M., Page, R.C., Misra, S., Plow, E.F. and Qin, J., Structure of an integrin IIb3 transmembrane-cytoplasmic heterocomplex provides insight into integrin activation. Proceedings of the National Academy of Sciences of the United States of America, 106(42), 17729-17734 (2009). PubMed ID 19895198.
Page, R.C., Moore, J.D., Lee, S., Opella, S.J. and Cross, T.A., Backbone structure of a small helical integral membrane protein: a unique structural characterization. Protein Science, 18(1), 134-146 (2009). PubMed ID 19177358.
Xu, Z., Page, R.C., Gomes, M.M., Kohli, E., Nix, J.C., Herr, A.B., Patterson, C. and Misra, S., Structural basis of nucleotide exchange and client binding by the novel Hsp70-cochaperone Bag2. Nature Structural and Molecular Biology, 15(12), 1309-1317 (2008). PubMed ID 19029896.
Tejero, J., Biswas, A., Wang, Z.-Q., Page, R.C., Haque, M.M., Hemann, C., Zweier, J.L., Misra, S. and Stuehr, D.J., Stabilization and characterization of a compound 1-like reaction intermediate in a heme-proximal mutant of nitric oxide synthase. Journal of Biological Chemistry, 283, 33498-33507 (2008). PubMed ID 18815130.
Page, R.C., Kim, S. and Cross, T.A., Transmembrane helix uniformity examined by spectral mapping of torsion angles. Structure, 16, 787-797 (2008). PubMed ID 18462683.