Gülmez Karaca Lab

Our ability to acquire and retain memories is essential for survival. Memories shape not only our personal identity but also enable us to plan for the future. The devastating impact of memory-related disorders, such as Alzheimer’s disease and PTSD, highlights the need of understanding the underlying these processes. Yet, the mechanisms by which memories are formed, stored, and retrieved in the brain remain elusive.

Our lab investigates how and where memories are encoded in the brain, from individual synapses to across systems in both healthy and pathological conditions. We focus on long-term dynamics of neuronal (micro)circuits and their connectivity patterns that underlie memory – so called memory engrams-, and how these are regulated by (epi)genetic factors and external influences such as stress, emotional arousal, time, and environmental changes.

To address these questions, we implement a multidisciplinary approach that integrates molecular biology, behavioral analysis in rodents, AAV-mediated gene delivery, pharmacological interventions, and high-resolution imaging of cells and synaptic connectivity. We also aim at developing (novel) AAV-based tools for activity-dependent tagging and manipulation of genetically defined neuronal populations to advance our understanding of memory circuitry and inform therapeutic strategies for neurological disorders involving abnormal circuit activity.

Group Members

Kübra Gülmez Karaca

PI

I am driven to understand how memories are formed, stored, and retrieved in the brain by investigating the long-term dynamic of memory-encoding circuits (engrams). I combine the use of molecular, behavioral, and viral tools, and imaging approaches in rodents.

Rodent behavioral analysis, viral gene delivery, structural plasticity, high-resolution microscopy, fiber photometry

Liselotte de Lange

Research Analyst

I am an Animal Technician (Research Analyst) at the Gülmez Karaca Lab, supporting research aimed at understanding memory, specifically how memories are stored, retrieved, and formed, using rodent models.

Rodent behavioral analysis, stereotactic surgery, animal management, immunohistochemistry, analysis

Publications

• Gulmez Karaca, K.^#, Bahtiyar, S., Dongen, L.V., Wolf, O.T., Hermans E.J., Henckens, M.J.A.G., Roozendaal, B. (2025) Posttraining noradrenergic stimulation maintains hippocampal engram reactivation and episodic-like specificity of remote memory. Neuropsychopharmacology, doi: 10.1038/s41386-025-02122-2. #Corresponding author. Open Access
• Gulmez Karaca, K., Kupke, J., Brito, D.V.C., Zeuch, B., Thome, C., Weichenhan, D., Lustik, P., Plass, C., Oliveira, A.M.M. (2020) Neuronal ensemble-specific DNA methylation strengthens engram stability. Nature Communications, 11, 639, doi: 10.1038/s41467-020-14498-4. Open Access.
• Gulmez Karaca, K., Brito, D.V.C., Kupke, J., Zeuch, B., Oliveira, A.M.M. (2021) Engram reactivation during memory retrieval predicts long-term memory performance in aged mice. Neurobiology of Aging, 101, 256-261. doi:10.1016/j.neurobiolaging.2021.01.019
• Bahtiyar, S., Gulmez Karaca, K., Henckens, M. J. A. G., Roozendaal, B. (2020) Norepinephrine and glucocorticoid effects on the brain mechanisms underlying memory accuracy and generalization. Molecular and Cellular Neuroscience, 108. doi: 10.1016/j.mcn.2020.103537.
• Gulmez Karaca, K., Kupke, J., Oliveira, A.M.M. (2021) Molecular and cellular mechanisms of engram allocation and maintenance. Brain Research Bulletin, 170, 274-282. doi: 10.1016/j.brainresbull.2021.02.01