Grant Mastick

Co-Director of Undergraduate BS Neuroscience Program, Professor
Headshot of Grant Mastick


To build a brain, the embryo must produce a spatially organized array of a vast number of neurons, then interconnect them. Our research group uses genetic and molecular approaches in mouse and chick embryos to investigate the functions of specific genes in brain development. This research has implications for the molecular therapy of neurological disease and injury, and is funded by the National Institutes of Health.

Our current research is on the migration of neurons and their axons through the developing brain. We investigate how molecular signals guide axons to migrate precisely long distances on longitudinal pathways, how cranial nerves grow out to connect to muscles, and also how neuron cell bodies settle in specific positions.  Our studies focus on a system of signals, the Slit/Robo repellents and the Netrin attractants, to understand the mechanisms by which opposing signals are integrated by neurons.

Research areas

Neuroscience; Genetics; Cell Biology; Developmental Biology


  • Alma College, MI, B.S. Biology, Chemistry, 1986
  • Carnegie Mellon University, Ph.D. Biological Sciences, 1992
  • University of Michigan, Postdoctoral Fellow, Developmental Neurobiology, 1992-1998

Currently in the Mastick lab

  • Minkyung Kim, PhD.  Research Assistant Professor.  Motor neuron migration; Longitudinal axon guidance.
  • Claudia Garcia Pena, PhD. Postdoctoral Fellow. Oculomotor neuron development and migration.
  • Sarah Barnum, technician.
  • Jennifer Li, Biology major. Axon guidance.
  • Chase Johnson, undergraduate. Axon guidance.
  • Sterling Louw, undergraduate. Axon guidance.

Recent graduates

  • Brielle Bjorke, PhD, Biochemistry. Postdoctoral Teaching Fellow, Carleton College, MN
  • Roland Watson, Biology BS.
  • Thijmen Sijnesael, visiting MS student, University of Raboud, Netherlands.
  • Clare Lee, Biology major. UCSF Dentistry.
  • Eric Robinson, BS/MS Biotechnology.
  • John Pietz, Chemistry and Music majors. United States Navy.
  • Christian Mohino, Biology major. PhD student, University of Nevada, Reno.
  • Michelle Vesser, Davidson High School student. University of Edinburgh.
  • Farnaz Shoja-Taheri, PhD, CMB. Postdoctoral fellow, Georgia.
  • Katherine Weller, MS, CMB. University of Nevada School of Medicine.
  • Hannah Jordan Gruner, MS, CMB. Postdoctoral fellow, UCSF.
  • Arielle Demarco, Biotechnology BS/MS. Hamilton, Reno.
  • Juliana Medeiros Oliveira, visiting Medical Student from Brazil. Spring 2015.
  • Marcelle Freire, visiting Medical Student from Universidade Federal de Sergipe, Brazil.
  • Siavash Mojibian, Neuroscience major. Pharmacy School, Rutgers.
  • Tatiana Fontelonga, Biotechnology BS/MS. PhD student, UNR.
  • Stacey Wong. Biochemistry BS/MD early admission; Class of 2015, UN School of Medicine.
  • Suman Gurung (Biotechnology BS/MS Degree Program, 2012.) PhD student, Biological Sciences, U Missouri.
  • Christine Schlemmer, Neuroscience BS, 2012. Class of 2016, UN School of Medicine.
  • Joshua Catapano, Biology BS, 2011. Class of 2016, UN School of Medicine.
  • Leila Nakhaee, Neuroscience BS 2013. Physician Assistant student, UC Davis.


  • Hannah Gruner, Minkyung Kim, and Grant S. Mastick. Robo1 and 2 repellent receptors cooperate to guide facial neuron cell migration and axon projections in the embryonic mouse hindbrain. In press, 2019, Neuroscience. doi: 10.1016/j.neuroscience.2019.01.017 PMID: 30685539.
  • Claudia Marcela García-Peña, Daniela Avila, Amaya Miquelajauregui, Lozano Flores Carlos, Grant S Mastick, Elisa Tamariz, Alfredo Varela-Echavarria. Neurophilic descending migration of dorsal midbrain neurons into the hindbrain. In press, 2018, Frontiers in Neuroanatomy. DOI: 10.3389/fnana.2018.00096
  • Riley Kellermeyer, Leah M. Heydman, Grant S. Mastick, Thomas Kidd. (2018). The Role Of Apoptotic Signaling In Axon Guidance. J Dev Biol. 2018 Oct 18;6(4). pii: E24. doi: 10.3390/jdb6040024. PMC6316149
  • Loic Fort, Jose Batista, Peter Thomason, Heather J. Spence, Jamie Whitelaw, Luke Tweedy, Jennifer Greaves, Kirsty J. Martin, Kurt I. Anderson, Peter Brown, Sergio Lilla, Matthew P. Neilson, Petra Tafelmeyer, Sara Zanivan, Shehab Ismail, David M. Bryant, Nicholas C.O. Tomkinson, Luke H. Chamberlain, Grant S. Mastick, Robert H. Insall and Laura M. Machesky. Fam49/CYRI interacts with Rac1 and locally suppresses protrusions. (2018). Nature Cell Biology, 20, 1159-1171 .
  • Kim, M., Fontelonga, T., Lee, C., Barnum, S., Mastick, G. S. (2017). Motor axons are guided to exit points in the spinal cord by Slit and Netrin signals. Developmental Biology, 432, 178-191.
  • Kyung-Tai Kim, Namhee Kim, Hwan-Ki Kim, Hojae Lee, Peter Gergics, Chungoo Park, Hannah N. Gruner, Grant S. Mastick, Hae-Chul Park, and Mi-Ryoung Song. ISL1-based LIM complexes control Slit2-dependent cranial motor neuron axon guidance. Scientific Reports, 2016 Nov 7; 6:36491. PMC5098159. doi: 10.1038/srep36491.
  • Brielle Bjorke, Farnaz Shoja-Taheri, Minkyung Kim, G. Eric Robinson, Tatiana Fontelonga, Kyung-Tai Kim, Mi-Ryoung Song and Grant S. Mastick. Contralateral migration of oculomotor neurons is regulated by Slit/Robo signaling. 2016. Neural Development 11: 18. PMC5075191 doi:10.1186/s13064-016-0073-y
  • Farnaz Shoja-Taheri, Arielle Demarco, and Grant S. Mastick. Post-crossing commissural axons are guided by Netrin1/DCC signals in the hindbrain. 2015. Journal of Neuroscience. 2015 Aug 19;35(33):11707-18. doi: 10.1523/JNEUROSCI.0613-15.2015. PMCID: PMC4540804
  • Hojae Lee, Minkyung Kim, Namhee Kim, Todd Mcfarlan, Samuel L. Pfaff , Grant S. Mastick, and Mi-Ryoung Song. Slit and Semaphorin signaling governed by Islet transcription factors positions motor neuron somata within the neural tube. 2015. Experimental Neurology. Jul;269:17-27. doi: 10.1016/j.expneurol.2015.03.024. PMC4446133
  • Minkyung Kim, Tatiana Fontelonga, Andrew P Roesener, Haeram Lee, Suman Gurung, Philipe RF Mendonca, and Grant S Mastick. Motor neuron cell bodies are actively positioned by Slit/Robo repulsion and Netrin/DCC attraction. 2015. Developmental Biology. 399 (1): 68-79. PMC4339514; doi: 10.1016/j.ydbio.2014.12.014
  • Minkyung Kim*, W. Todd Farmer*, Brielle Bjorke, Samuel A McMahon, Pierre J. Farbe, Frederic Charron, and Grant S. Mastick. Longitudinal axons navigate using a balance of Netrin attraction and Slit repulsion. 2014, Neural Development. 9:17 doi:10.1186/1749-8104-9-17 * Co-first authors. PMC4118263