Arthur E. Johnson

TAMHSC Arrows COM Arrows Basic Sciences Arrows Molecular & Cellular Medicine Arrows Faculty Arrows Arthur E. Johnson

Regents Professor
Wehner-Welch Chair
Distinguished Professor
Distinguished Professor of Chemistry
Department of Molecular and Cellular Medicine

Room 116 Reynolds Medical Building
College Station, Texas 77843
Phone: 979-862-3188
Fax: 979-862-3339
Email: ajohnson@medicine.tamhsc.edu
Lab Webpage: http://Wehner Welch Research Lab

Education and Post-Graduate Training

Dr. Johnson received a B.S. in Chemistry from the California Institute of Technology in 1964. After teaching and coaching football at Milton Academy near Boston for five years, he earned his Ph.D. in Chemistry at the University of Oregon in 1973. Following postdoctoral research at Columbia University on a Helen Hay Whitney Fellowship, he joined the faculty of the Department of Chemistry and Biochemistry at the University of Oklahoma in 1977, where he was named the Grayce B. Kerr Centennial Chair in 1992 before moving to Texas A&M in 1994. Dr. Johnson is a Texas A&M Regents Professor, a Distinguished Professor of Molecular and Cellular Medicine and holds the Wehner-Welch Foundation Chair in the College of Medicine at the Texas A&M Health Science Center. He is also a Distinguished Professor of Chemistry and a Professor of Biochemistry and Biophysics at Texas A&M University. Johnson has taught lecture and laboratory courses in biochemistry, biophysics, chemistry, and physics at various levels.

Research Interests

We are investigating several biochemical processes in my laboratory, including the movement of proteins through or into a membrane (protein trafficking), nascent protein folding, ER-associated degradation (ERAD) of misfolded proteins, and the creation of holes in mammalian cell membranes by bacterial toxins. Two other processes that we have examined extensively are blood coagulation and protein biosynthesis. The molecular machinery involved in each of these complex processes consists largely of multi-component complexes of proteins or of proteins and nucleic acids, most of which are membrane-bound. Our research and published work therefore includes studies of protein-membrane, protein-nucleic acid, protein-protein, and protein-metal ion interactions.

To examine how these processes are accomplished and regulated at the molecular level, we have employed a variety of biophysical, biochemical, and other techniques. Multiple fluorescence techniques are used to detect and characterize, both kinetically and thermodynamically, the molecular interactions and conformational changes involved in the assembly, function, and regulation of free and membrane-bound macromolecular complexes, as well as to determine their structure and topography.We also use fluorescence resonance energy transfer (FRET), photocrosslinking, and chemical crosslinking to detect nascent protein folding, to determine the spatial arrangement of individual components within the complexes, to identify which components or residues are adjacent to each other, and to quantify the magnitude of conformational changes in the complexes. Importantly, all of our biophysical experiments examine functional molecules in fully assembled multi-component complexes in intact membranes in aqueous solution so that we can directly correlate structure and function.

Selected Publications

Saksena, S., Summers, M. D., Burks, J. K., Johnson, A. E., and Braunagel, S. C. (2006) “Importin alpha-16: a Translocon-Associated Protein that May Facilitate Sorting of Integral Membrane Proteins to the Nuclear Envelope,” Nature Struct Mol Biol 13, 500-508.

Woolhead, C. A., Johnson, A. E., and Bernstein, H. D. (2006) “Translation Arrest Requires Two-Way Communication between a Nascent Polypeptide and the Ribosome,” Mol. Cell 22, 587-598.

Wahlman, J., DeMartino, G. N., Skach, W. R., Bulleid, N. J., Brodsky, J. L., and Johnson, A. E. (2007) "Real-time Fluorescence Detection of ERAD Substrate Retro-translocation in a Mammalian In Vitro System". Cell 129, 943-955.

Lakkaraju, A. K. K., Mary, C., Scherrer, A., Johnson, A. E., and Strub, K. (2008) "SRP Maintains Nascent Chains Translocation-Competent by Slowing Translation Rates to Match Limiting Numbers of Targeting Sites". Cell, 133 (3), 440-451.

Alder, N. N., Jensen, R. E., and Johnson, A. E. (2008) "Fluorescence Mapping of Mitochondrial TIM23 Complex Reveals a Water-Facing, Substrate-Interacting Helix Surface". Cell 134. 439-450.

Saksena, S., Wahlman, J., Teis, D., Johnson, A. E.,* and Emr, S. D.* (2009) "Functional Reconstitution of ESCRT-III Assembly and Disassembly". Cell 136, 97-109. (* = co-corresponding authors)

Berndt, U., Oellerer, S., Zhang, Y., Johnson, A. E., and Rospert, S. (2009) "A Signal-Anchor Sequence Stimulates Signal Recognition Particle Binding to Ribosomes from Inside the Exit Tunnel". Proc. Natl. Acad. Sci. (USA) 106, 1398-1403. (PMCID 19164516

Farrand, A. J., LaChapelle, S., Hotze, E., Johnson, A. E., and Tweten, R. K. (2010) "Only Two Amino Acids Are Essential for Cytolytic Toxin Recognition of Cholesterol at the Membrane Surface". Proc. Natl. Acad. Sci. (USA) 107, 4341-4346.

Khushoo, A., Yang, Z., Johnson, A.E., and Skach, W.R. (2011) "Ligand-Driven Vectorial Folding of Ribosome-Bound Human CFTR NBD1". Mol. Cell 41, 682-692.

Devaraneni, P., Conti, B., Matsumura, Y., Yang, Z., Johnson, A. E., and Skach, W. R.* (2011) “Stepwise Insertion and Inversion of a Type II Signal Anchor Occurs in the Ribosome-Sec61 Complex,” Cell 146, 134-147.

Lin, P.-J., Jongsma, C. G., Liao, S., and Johnson, A. E. (2011) "Transmembrane Segments of Nascent Polytopic Membrane Proteins Control Cytosol/ER Targeting during Membrane Integration ," J. Cell Biol. 195, 41-54.

Lin, P.-J., Jongsma, C. G., Pool, M. R., and Johnson, A. E. (2011) "Polytopic Membrane Protein Folding at L17 in the Ribosome Tunnel Initiates Cyclical Changes at the Translocon," J. Cell Biol. 195, 55-70.