Basic Research

Team 3: Molecular Biology

Principal Investigator

Joseph Stephan, PhD
Assistant Professor of Biochemistry
Gilbert and Rose-Marie Chagoury School of Medicine
Lebanese American University, Byblos Campus
Office: 4721
Telephone: +961 9 547254, ext. 2845

Research Expertise and Interests

My research team is interested in the molecular basis of memory and learning, as well as the impact of physiological activities such as exercise and its metabolites on these cognitive processes. This has led us to focus on prions. Identified initially in the context of diseases such as Creutzfeld Jacob and Kuru, these shape-shifting proteins appear to play a wide variety of roles in different physiological contexts such as long-term memory storage, autophagy and cancer. Using mouse models, neuronal cultures, and the powerful biochemical and molecular arsenal of the budding yeast S. cerevisiae, we attempt to elucidate the role of prions in learning and memory.

Team members and Collaborators

The laboratory also benefits from additional collaborations with LAU researchers and with investigators at outside universities.

Selected Publications

Khalifeh M, Hobeika R, El Hayek L, Saad J, Eid F, El-Khoury R, Ghayyad L-M, Jabre V, Nasrallah P, Barmo N, Stephan JS, Khnayzer R, Khalil C, Sleiman SF (2020). Nicotine induces resilience to chronic social defeat stress in a mouse model of water pipe tobacco exposure by activating BDNF signaling. Behav. Brain Res., Epub Jan 21.

Stephan JS and Sleiman SF (2019). Exercise factors as potential mediators of cognitive rehabilitation following traumatic brain injury. Curr Opin Neurol. 2019 Dec; 32(6):808-814.

El Hayek L, Khalifeh M, Zibara V, Abi Assaad R, Emmanuel N, Karnib N, El-Ghandour R, Nasrallah P, Bilen M, Ibrahim P, Younes J, Abou Haidar E, Barmo N, Jabre V, Stephan JS, Sleiman SF. (2019) Lactate Mediates the Effects of Exercise on Learning and Memory through SIRT1-Dependent Activation of Hippocampal Brain-Derived Neurotrophic Factor (BDNF). J Neurosci. 2019 Mar 27;39(13):2369-2382. Epub Jan 28.

Stephan J.S., Fioriti L., Lamba N., Colnaghi L., Karl K., Derkatch I.L. and Kandel E.R. (2015) The CPEB3 protein is a functional prion that interacts with the actin cytoskeleton. Cell Reports. 2015 Jun 23;11(11):1772-85. Impact Factor: 7.2

Fioriti L., Myers C., Huang Y.Y., Li X., Stephan J.S., Trifilieff P., Kosmidis S., Drisaldi B., Pavlopoulos E., Kandel E.R. (2015) The Persistence of Memory and its Reconsolidation Require CPEB3-Mediated Protein Synthesis in the Hippocampus Neuron. 2015 Jun 17;86(6):1433-48. Impact Factor: 16.2


Intramural LAU Graduate Studies and Research Office (GSR) Grant - term concluded, CNRS Grant - term concluded; Intramural Continuing Professional Development funds; Intramural GSR Cluster Grants; additional pending applications.