Jim Trimmer


Position Title
Distinguished Professor

Department of Physiology and Membrane Biology, School of Medicine


Research Interests

Cell signaling in mammalian neurons, neuronal cell biology, membrane protein trafficking and function, affinity reagent development and validation

Grad Group Affiliations

  • Biochemistry, Molecular, Cellular and Developmental Biology
  • Molecular, Cellular and Integrative Physiology

Specialties / Focus

  • Cell Biology
  • Neurobiology
  • Tool development
  • Proteomics


  • NPB 107 Cell Signaling in Health and Disease, Winter


  • 4103/4107 Tupper Hall
    • Jessica Alexis Okomura Bernal (undergraduate student), Rebecca Boulden (undergraduate student), Nhi Bui (undergraduate student), Karen Cornejo (undergraduate student, UCLEADS scholar), Belvin Gong (staff research associate), Kandacharan Karthik  (undergraduate student), Doyean (Amy) Lee (undergraduate student), Karl Murray (assistant adjunct professor), Deborah van der List (staff research associate),  Nick Vierra (postdoc, NRSA fellow), Chih-Chuan Wang (postdoc)

Honors and Awards

  • 2000-2007 Jacob Javits Neuroscience Investigator (MERIT) Award, National Institute of Neurological Disorders and Stroke, National Institutes of Health
  • 1994-1999 Established Investigatorship, American Heart Association

    Professional Societies

    • Society for Neuroscience
    • American Society for Cell Biology


    • 1987 PhD (Marine Biology) University of California, San Diego/Scripps Inst. Oceanography
    • 1981 BA (Biology) University of California, San Diego

    Publications (since 2016)

    Kirmiz, M., Gillies, T. E., Dickson, E. J., and J. S. Trimmer. (2019). Neuronal ER-PM Junctions Organized by Kv2-VAP Pairing Recruit Nir Proteins and Affect Phosphoinositide Homeostasis.  J. Biol. Chem. 294: 17735-17757. 

    Vierra, N. C., Kirmiz, M., van der List, D., Santana, L. F., and J. S. Trimmer. (2019). Kv2.1 Mediates Spatial and Functional Coupling of L-type Calcium Channels and Ryanodine Receptors in Neurons. eLife 8:e49953.

    Foote, K. M., Lyman, K. A., Han, Y., Michailidis, I. E., Heuermann, R. J., Mandikian, D., Trimmer, J. S., Swanson, G.T., and D. M. Chetkovich. (2019). TRIP8b Phosphorylation is Altered in an Animal Model of Temporal Lobe Epilepsy and Modulates HCN Channel Function. J. Biol. Chem. 294:15743-15758. 

    Litvina, E., Adams, A., Barth, A., Bruchez, M., James, C., Dupre, K., Frank, L., Gates, K., Harris, K., Joo, H., Lichtman, J., Ramos, K., Sejnowski, Trimmer, J. S., White, S., and W. Koroshetz. (2019). BRAIN Initiative: Cutting-edge Tools and Resources for the Community.  J. Neurosci. 39:8275-8284. 

    Dong, J.-X., Lee, Y., Kirmiz, M., Palacio, S., Dumitras, C., Moreno, C. M., Sando, R., Santana, L. F., Südhof, T. C., Gong, B., Murray, K. D., and J. S. Trimmer. (2019). A Toolbox of Nanobodies Developed and Validated for Diverse Neuroscience Research Applications.  eLife 8:e48750. 

    Sato, D., Hernández-Hernández, G., Matsumoto, C., Tajada, S., Moreno, C. M., Dixon, R. E., O'Dwyer, S., Navedo, M. F., Trimmer, J. S., Clancy, C. E., Binder, M. D., and L. F. Santana. (2019). A Stochastic Model of Ion Channel Cluster Formation in the Plasma Membrane. J. Gen. Physiol. 151:1116-1134.

    Zheng, Y., Liu, P., Bai, L., Trimmer, J. S., Bean, B. P., and D. D. Ginty. (2019). Deep Sequencing of Somatosensory Neurons Reveals Molecular Determinants of Intrinsic Physiological Properties. Neuron 103:598-616.

    Andrews, N. P., Boeckman, J. X., Manning, C. F., Nguyen, J. T., Bechtold, H., Dumitras, C., Gong, B., Nguyen, K., van der List, D., Murray, K. D., Engebrecht, J. and J. S. Trimmer. (2019). A Toolbox of IgG Subclass-Switched Recombinant Monoclonal Antibodies for Enhanced Multiplex Immunolabeling of Brain. eLife 8:e43322.

    Kirmiz, M., Palacio, S., Thapa, P., King, A. N., Sack, J. T. and J. S. Trimmer. (2018). Remodeling Neuronal ER-PM Junctions is a Conserved Nonconducting Function of Kv2 Plasma Membrane Ion Channels. Mol. Biol. Cell 29: 2410-2432.

    Kirmiz, M., Vierra, N. C., Palacio, S., and J. S. Trimmer. (2018). Identification of VAPA and VAPB as Kv2 Channel-Interacting Proteins Defining Endoplasmic Reticulum-Plasma Membrane Junctions in Mammalian Brain Neurons. J. Neurosci. 38: 7562-7584.

    Taussig, M. J., Fonseca, C., and J. S. Trimmer. (2018). Antibody Validation: A View from the Mountains. New Biotech. 45:1-8.

    Baba, K., Yoshida, W., Toriyama, M., Shimada, T., Manning, C. F., Kohno, K., Trimmer, J. S., Watanabe, R., and N. Inagaki. (2018). Gradient-Reading and Mechano-Effector Machinery for Netrin-1–Induced Axon Guidance. eLife 7. pii: e34593.

    Simhal, A. K., Gong, B., Trimmer, J. S., Weinberg, R. J., J. Smith, S. J., Sapiro, G., and K. D. Micheva. (2018). Automated Antibody Characterization and Screening for Array Tomography via Probabilistic Synapse Detection. Front. Neuroanat. 12:51.

    Bradbury, A. R. M., Trinklein, N. D., Thie, H., Wilkinson, I. C., Tandon, A. K., Anderson, S., Bladen, C. L., Jones, S., Force Aldred, S., Bestagno, M., Burrone, O., Maynard, J., Ferrara, F., Trimmer, J. S., Görnemann, J., Glanville, J., Wolf, P., Frenzel, A., Wong. J., Yu, X., Eng, H.-Y., Lane, D, Lefranc, M.-P., Clark, M., & Dübel, S. (2018). When Monoclonal Antibodies are not Monospecific: Hybridomas Frequently Express Additional Functional Variable Regions. mAbs 27:1-19.

    Riquelme, D., Silva, I., Philp, A. M., Huidobro-Toro, J. P., Cerda, O., Trimmer J. S., and E. Leiva-Salcedo. (2018). Subcellular Localization and Activity of TRPM4 in Medial Prefrontal Cortex Layer 2/3. Front. Cell. Neurosci. 12: 12.

    Bishop, H. I., Cobb, M. M., Kirmiz, M., Parajuli, L., Mandikian, D., Philp, A. M., Melnik, M., Kuja-Panula, J., Rauvala, H., Shigemoto, R., Murray, K. D., and J. S. Trimmer. (2018). Kv2 Channels Determine the Expression and Localization of the Associated AMIGO-1 Cell Adhesion Molecule in Adult Brain Neurons. Front. Mol. Neurosci. 11: 1.

    Jensen, C. S., Watanabe, S., Stas, J. I., Klaphaak, J., Schmitt, N., Olesen, S.-P., Trimmer, J. S., Rasmussen, H. B., and H. Misonou. (2017). Trafficking of Kv2.1 Channels to the Axon Initial Segment by a Novel Non-Conventional Secretory Pathway. J. Neurosci. 37:11523-11536.

    Speca, D. J., Trimmer, J. S., Peterson, A. S., and E. Diaz. (2017). Whole Exome Sequencing Reveals a Functional Mutation in the GAIN Domain of the Bai2 Receptor Underlying a Forward Mutagenesis Hyperactivity QTL. Mammalian Genome 28:465-475. 

    Palacio, S., Chevaleyre, V., Brann, D. H., Murray, K. D., Piskorowski, R. A., and J. S. Trimmer. (2017). Heterogeneity in Kv2 Channel Expression Shapes Action Potential Characteristics and Firing Patterns in CA1 Versus CA2 Hippocampal Pyramidal Neurons eNeuro 4(4).

    Gong, B., Murray, K. D., and J. S. Trimmer. (2016). Developing High-Quality Mouse Monoclonal Antibodies for Neuroscience Research – Approaches, Perspectives and Opportunities. New Biotech. 33: 551-564.

    Kirk, L. M., Ti, S. W., Bishop, H. I., Llamas-Orozco, M., Pham, M., Trimmer, J. S., and E. Diaz. (2016). Distribution of the SynDIG4/Proline Rich Transmembrane Protein 1 in Rat Brain. J. Comp. Neurol524:2266-2280.


    For a complete list of publications see: http://www.ncbi.nlm.nih.gov/pubmed/?term=trimmer+js