Advanced Imaging Core

National Institute On Deafness And Other Communication Disorders

Investigators

Linked publications, trials & patents

Abstract

The AIC team consists of Director Dr. Dennis C. Winkler and Dr. Yuliya Sokolova. The core is dedicated primarily to collaborating with and training scientists in NIDCD in studies utilizing various forms of transmission electron microscopy (TEM) and focused ion-beam scanning electron microscopy (FIB-SEM). Occasionally, the AIC also collaborates with and trains researchers from other NIH institutes. In addition, Dr. Winkler has reviewed manuscripts, grants, and various documents for NIDCD PIs, served as a reviewer for submitted journal manuscripts, written letters of recommendation, and served on several NIH committees. The electron microscopes available to the core and its users are a JEOL JEM-2100 200kV transmission electron microscope with a Gatan OneView camera, a Thermo Fisher/FEI Titan Halo 300 kV transmission electron microscope with scanning and phase plate capabilities and Ceta and Falcon 3EC cameras, and a TESCAN Amber focused ion-beam scanning electron microscope primarily for FIB-SEM Tomography projects where 3D volume reconstructions on the cellular and sub-cellular levels are desired. The core works with and trains personnel in conventional EM, cryo-EM, cryo-ET, and FIB-SEM related techniques as well as in the use of electron microscopes and ancillary electron microscopy equipment. Much of the core’s work involves the study of auditory structures using conventional TEM and FIB-SEM. High pressure freezing, freeze-substitution, and sectioning are sample preparation offerings. This conventional EM workflow is used for better preservation of the native state of cellular structures and, particularly, antigenic sites for immune EM. On an infrastructure note, the combined efforts of the AIC and the NIH’s Office of Research Facilities team have finally resolved all issues associated with the Titan Halo electron microscope room renovation, the final correction being related to the room’s dehumidifier. NIDCD Projects: Section on Sensory Physiology and Biophysics (Dr. Angela Ballesteros): The AIC worked with Drs. Angela Ballesteros and Hubert Lee on cryo-EM imaging of liposomes containing TMC1 and TMC2, mechanoelectrical transducer (MET) channel proteins, and negative stain imaging of TCM1 samples in preparation for cryo-EM work. Section on Human Genetics (Dr. Thomas Friedman): The core continued collaborating with the Section on Human Genetics, working closely with Drs. Inna Belyantseva and Takushi Miyoshi (now at Southern Illinois University School of Medicine) on various TEM projects including ultrastructural analysis of the Organ of Corti focusing on fine structure of inner and outer hair cells in wild-type and knockout mice, the localization of proteins in thin sections of the Organ of Corti by immunostaining, and TEM visualization of ultrastructure alterations in inner and outer hair cells in taperin-deficient mice. While the latter work is still ongoing, it has resulted in a publication titled “Taperin bundles F-actin at stereocilia pivot-points enabling optimal lifelong mechanosensitivity” in J. Cell Biol. (see [1] in report bibliography). Section on Omics and Translational Science of Hearing (Dr. Ronna Hertzano): The core continued its collaboration with the Section on Omics and Translational Science of Hearing involving the ultrastructural analysis of kinocilium in Rfx-/- mice mutants, working with Drs. Ronna Hertzano, Katie Gwilliam, Beatrice Milon, and Lesly Umanzor as well as Dr. Inna Belyantseva of the Section on Human Genetics. We will soon consider the use of FIB-SEM tomography in this study. Section on Inner Ear Therapeutics (Dr. Michael Hoa): After wrapping up the previous study of endolymphatic hydrops in the Slc26a4-insufficiency DOX-ERKO mouse model, the core has started a new project with Drs. Michael Hoa and Rafal Olszewski using TEM and FIB-SEM tomography to investigate stria vascularis ultrastructure. Section on Structural Cell Biology (Dr. Bechara Kachar): The core worked on the freeze substitution and sectioning for the TEM study of hydra with Dr. Bechara Kachar. The core also assisted Drs. Kachar and Amirrasoul Tavakoli Targhi with the use of the Titan Halo transmission electron microscope as well as the SerialEM automated data acquisition software package. Section on Sensory Cell Development and Function (Dr. Katie Kindt): The core’s work with Drs. Katie Kindt and Sandeep David studying zebrafish hair cells, phenotypic characterization of zebrafish, and mice kinesin mutants culminated in the publication “Kif1a and intact microtubules maintain synaptic-vesicle populations at ribbon synapses in zebrafish hair cells” in J. Physiol. (see [2] in report bibliography). Projects with Other NIH Institutes: NEI/Transmission Electron Microscopy Unit: The NEI occasionally makes use of the AIC’s capabilities when resources allow. The core worked with Dr. Wendy Bautista Guzman, NEI’s Transmission Electron Microscopy Unit Chief, acquiring tomographic tilt series on sections of plastic embedded specimens of interest on the AIC’s JEM-2100. Dr. Guzman has since left the NIH. NIAMS/Protein Expression Laboratory: Negative stain imaging was performed on Rev and NAP proteins and complexes of both for Drs. Elif Eren and Norman Watts of NIAMS’s Protein Expression Laboratory. Publications from Projects Under Previous Core Director, Dr. R.S. Petralia: Soto F, Lin CI, Jo A, et al. Molecular mechanism establishing the OFF pathway in vision. Nat Commun 16, 3708 (2025). https://doi.org/10.1038/s41467-025-59046-0 Lee HJ, Fenollar-Ferrer C, Isgrig K, Wang YX, Valente K, Eide J, Honda K, Chien WW, Petralia RS, Dong L, Friedman TB, Bonifacino JS, Griffith AJ, Roux I. SLC26A4-AP-2 mu2 interaction regulates SLC26A4 plasma membrane abundance in the endolymphatic sac. Sci Adv. Oct 11;10(41) (2024). https://doi.org/10.1126/sciadv.adm8663