Jorge Sierra Fonseca

Photo of Jorge Sierra Fonseca
Assistant Professor of Neuroscience
Office: Buhl 132 | Lab: Buhl 116

Hometown: Juarez, Mexico
Joined Chatham: 2021


Family, reading, cooking, gardening


I was born in the city of Juarez, Mexico, and grew up in the El Paso, Texas-Juarez binational metropolitan area. From a young age, I have been fascinated by the life sciences, which is why I majored in biology at the Autonomous University of Juarez. As an undergraduate student, I had the opportunity to join a biochemistry research lab during my freshman year, where I used calcium-transporting enzymes as model systems to study the toxic effects of drugs and environmental pollutants. I later joined the doctoral program in pathobiology at the University of Texas at El Paso (UTEP), where my dissertation focused on studying how intracellular signaling molecules called G proteins regulate the assembly and organization of the neuronal cytoskeleton, using neuronal cells in culture. I later joined a neuropathology research lab at Harvard Medical School as a postdoctoral fellow, where I used the fruit fly Drosophila to study how disruption of specific cellular pathways can lead to neurodegeneration, a phenomenon seen in neurological disorders such as Alzheimer’s and Parkinson’s diseases. I later returned to UTEP for another postdoctoral appointment, where I used rodents as preclinical models to study how chronic stress can alter protein degradation pathways in the brain, how this is connected to the development of neurological disorders and devising potential therapeutic interventions.


Research at my Cellular and Molecular Neurobiology Lab focuses on studying chronic stress and its neurochemical effects on the brain. Stress is an inevitable component of our modern lifestyle, and it has been identified as a key factor in the development of neurodegenerative disorders. My research aims to determine how chronic stress can modify specific cellular and molecular pathways to predispose individuals to suffering from a neurological disorder later in life.

I use both in vitro and in vivo approaches to conduct my research. The SH-SY5Y neuroblastoma cell line, a widely validated model in neurobiology, is employed as a cellular model of chronic stress in combination with stress hormones. Also, in collaboration with Dr. Kelly Lohr (Washington & Jefferson College), research in my lab uses the fruit fly, Drosophila, as a powerful genetic model to study the effects of stress on human neurodegenerative diseases (i.e., tauopathies). In addition, through ongoing collaborations derived from my postdoctoral work, rat brain tissue from chronically stressed animals is used to study the persistent effects of early-life adversity on neuronal signaling pathways.

Students interested in joining the Cellular and Molecular Neurobiology Lab at Chatham University should contact Dr. Sierra.

  • Mary S. and John Kostalos, Jr. Foundation award. Chatham University, 2022.
  • Research and Sabbatical funding award. Chatham University, 2021 and 2022.
  • VIDA: CARTT postdoctoral fellow, National Institute on Drug Abuse, University of Texas at El Paso, 2018-2020.
  • Academic and Research Excellence Award. University of Texas at El Paso, 2014.
  • Pan American Round Table of El Paso Scholarship, 2011-2013.
  • American Society for Cell Biology Graduate Student Travel Award, 2012.
  • College of Science Travel Award. University of Texas at El Paso, 2008, 2010, and 2012.
  • Graduate School Research Support Award. University of Texas at El Paso, 2009.
  • Graduate School Travel Award. University of Texas at El Paso, 2008 and 2010.
  • Academic Effort Award. Autonomous University of Juarez, 2005-2007.
  • Gosselik, K.L., Sierra-Fonseca, J.A., Jezova, D. (2022). Editorial: Stress, anxiety, and the synapse. Frontiers in Behavioral Neuroscience.
  • Hamdan, J.N., Sierra-Fonseca, J.A., Flores, R.J., Saucedo, S., Miranda-Arango, M., O’Dell, L.E., Gosselink, K.L. (2022). Early-life adversity increases anxiety-like behavior and modifies synaptic protein expression in a region-specific manner. Frontiers in Behavioral Neuroscience.
  • Sierra-Fonseca, J.A., Hamdan, J.N., Cohen, A.A., Cardenas, S.M., Saucedo, S., Lodoza, G.A., Gosselink, K.L. (2021). Neonatal maternal separation modifies proteostasis marker expression in the adult hippocampus. Frontiers in Molecular Neuroscience. 14: 661993. 
  • Sierra-Fonseca, J.A., Rodriguez, M., Themann, A., Lira, O., Flores-Ramirez, F.J., Vargas-Medrano, J., Bharathi, G., Iñiguez, S.D. (2021). Autophagy induction and accumulation of phosphorylated tau in the hippocampus and prefrontal cortex of adult C57BL/6 mice subjected to adolescent fluoxetine treatment. Journal of Alzheimer’s Disease. 83: 1691-1702.
  • Flores-Ramirez, F.J., Themann, A., Sierra-Fonseca, J.A., Garcia-Carachure, I., Castillo, S.A., Rodriguez, M., Lira, O., Preciado-Piña, J., Warren, B.L., Robison, A.J., Iñiguez, S.D. (2021). Adolescent fluoxetine treatment mediates a persistent anxiety-like outcome in female C57BL/6 mice that is ameliorated by fluoxetine re-exposure in adulthood. Scientific Reports. 11: 7758.
  • Sierra-Fonseca, J.A., Miranda, M., Das, S., Roychowdhury, S. (2021). The bg subunit of heterotrimeric G proteins interacts with actin filaments during neuronal differentiation. Biochemical and Biophysical Research Communications. 549: 98-104.
  • Grigoruta, M., Chavez-Solano, M., Varela-Ramirez, A., Sierra-Fonseca, J.A., Orozco-Lucero, E., Hamdan, J.N., Gosselink, K.L., Martinez-Martinez, A. (2020). Maternal separation induces retinal and peripheral blood mononuclear cell alterations across the lifespan of female rats. Brain Research. 1749: 147117.
  • Sierra-Fonseca, J.A., Parise, L.F., Flores-Ramirez, F.J., Robles, E.H., Garcia-Carachure, I., Iñiguez, S.D. (2019). Dorsal hippocampus ERK2 signaling mediates anxiolytic-related behavior in male rats. Chronic Stress. 3: 1-7.
  • Sierra-Fonseca, J.A., Gosselink, K.L. (2018). Tauopathy and neurodegeneration: a role for stress. Neurobiology of Stress. 9: 105-112.
  • Flores, I.E., Sierra-Fonseca, J.A., Davalos, O., Saenz, L.A., Castellanos, M.M., Zavala, J.K., Gosselink, K.L. (2017). Stress alters the expression of cancer-related genes in the prostate. BMC Cancer. 17: 621.
  • Sierra-Fonseca. J.A., Najera, O., Martinez-Jurado, J., Walker, E.M., Varela-Ramirez, A., Khan, A.M., Miranda, M., Lamango, N.S., Roychowdhury, S. (2014). Nerve growth factor induces neurite outgrowth of PC12 cells by promoting Gbg-microtubule interaction. BMC Neuroscience. 15: 3798.