Tiffany Schmidt

Schmidt completed her undergraduate studies at Luther College in Decorah, Iowa in 2006, receiving a Bachelor of Arts in Biology and Honors Psychology. Schmidt then began as an assistant professor at Northwestern University in the Department of Neurobiology in 2014. Schmidt continued in this role until 2020, when she was appointed as an associate professor in the Department of Neurobiology, with a secondary appointment in the Department of Ophthalmology. == Research contributions ==

Changes in ipRGC light responses during development As a graduate student in the laboratory of Paulo Kofuji at the University of Minnesota, Schmidt's research focused on analyzing intrinsically photosensitive retinal ganglion cells (ipRGCs) at the single-cell level to determine how ipRGCs relay light information to the brain. In early experiments, Schmidt and colleagues created a transgenic mouse line in which the melanopsin promoter drives the expression of enhanced green fluorescent protein (EGFP). The intrinsic phototransduction pathway was mediated by melanopsin, while the extrinsic pathway utilized retinal rod and cone systems. The ability to label ipRGCs with EGFP also allowed Schmidt and her colleagues to specify the morphology and location of three ipRGC subpopulations within the inner plexiform layer of the retina. Functional differences between M1 and M2 ipRGCs In 2009, Schmidt and Kofuji utilized the same transgenic mouse line to label ipRGCs in vivo with EGFP Role of melanopsin and ON alpha RGCs on image-forming vision In 2014, as a postdoctoral fellow in the laboratory of Samer Hattar at Johns Hopkins University, Schmidt and colleagues used immunohistochemistry to identify that a subset of retinal ganglion cells, ON alpha RGCs, express a melanopsin reporter. This study also identified the role of melanopsin in contrast detection, an important aspect of image-forming vision. Schmidt and Hattar used an optokinetic tracking assay to determine that Opn4-/- mice showed reduced contrast sensitivity. Deficits in contrast sensitivity were significantly worsened in a mouse model in which ON alpha RGCs were ablated. These results demonstrate that melanopsin and ON alpha RGCs play a role in image-forming vision by regulating contrast sensitivity. == Awards and achievements ==

Over the course of her career, Schmidt has received several awards for her work. As a graduate student at the University of Minnesota, she won the Morris Smithberg Memorial Prize from the Graduate Program in Neuroscience in 2007 which is granted to the best performing student on first-year courses and the final written exam. Additionally, she won the Milne and Brandenburg Research Award in 2010 which is awarded to students for their thesis research in the biomedical sciences. In her thesis, Schmidt studied the properties and morphology of ipRGCs. The award is given to new researchers whose projects show potential to have wide-ranging impacts. In 2016, Schmidt won the Karl Kirchgessner Foundation Vision Research Grant which is a foundation that primarily supports disadvantaged individuals but also grants money for new research in vision. In 2016, she won the Klingenstein-Simons Fellowship Award in the Neurosciences for her work in light-driven behavior. Additionally, in 2017 she won the Sloan Research Fellowship Award in Neuroscience which is a two-year $75,000 fellowship granted to young researchers, and in 2019 she was a recipient of the Brain Research Fay/Frank Seed Grant which funds neuroscience research. She received the Pisart Award for Outstanding Achievements in Vision Science in 2019. In 2020, Schmidt won the Junior Faculty Award from the Society for Research on Biological Rhythms for her exceptional work in the chronobiology field. == Current laboratory research and focuses ==

Recent grants and publications Currently, Schmidt is still conducting research in her lab at Northwestern University. In 2020, Schmidt earned tenure and was promoted to associate professor at Northwestern. Also in 2020, the Schmidt Lab received the Chicago Biomedical Research Consortium Catalyst Award which provided funding for further laboratory research in chronobiology. and have further explored the diversity of ipRGC functions. functions of M4 and M5 ipRGCs, cellular properties of ipRGCs in postnatal development, and using single-cell RNA sequencing to determine subsets of retinal ganglion cells. Selected recent publications Source: • Laboissonniere, Lauren A.; Sonoda, Takuma; Lee, Seul K; Trimarchi, Jeffrey M.; Schmidt, Tiffany M. Single-cell RNA-Seq of Defined Subsets of Retinal Ganglion Cells. Journal of Visualized Experiments (123): 55229 (2017). • Rupp, Alan C.; Ren, Michelle; Altimus, Cara M.; Fernandez, Diego C.; Richardson, Melissa; Turek, Fred; Hattar, Samer; Schmidt, Tiffany M. Distinct ipRGC subpopulations mediate light's acute and circadian effect on body temperature and sleep. eLife 8:e44358 (2019). • Sonodoa, Takuma; Okabe, Yudai; Schmidt, Tiffany M. Overlapping morphological and functional properties between M4 and M5 intrinsically photosensitive retinal ganglion cells. Journal of Comparative Neurology 528 (6): 1028-1040 (2019). • Lucas, Jasmine A.; Okabe, Yudai; Schmidt, Tiffany M. Cellular properties of intrinsically photosensitive retinal ganglion cells during postnatal development. Neural Development 14 (1): 8 (2019). • Sonoda, Takuma; Li, Jennifer Y.; Hayes, Nikolas W.; Chan, Jonathan C.; Okabe, Yudai; Belin, Stephane; Nawabi, Homaira; Schmidt, Tiffany M. A noncanonical inhibitory circuit dampens behavioral sensitivity to light. Science 368 (6490): 527-531 (2020). • Aranda, Marcos L.; Schmidt, Tiffany M. Diversity of intrinsically photosensitive retinal ganglion cells: circuits and functions. Cellular and Molecular Life Sciences 78 (3): 889-907 (2021). • Contreras, Ely; Sonoda, Takuma; Birnbaumer, Lutz; Schmidt, Tiffany M. Melanopsin activates divergent phototransduction pathways in ipRGC subtypes. bioRxiv (2022). == References ==