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Alexander J. Travis, VMD, Ph.D.

Associate Professor of Reproductive Biology

Dr. Alex Travis’s lab explores a diverse set of subjects, ranging from technologies based on the very smallest biological machines to inquiries in wildlife conservation and sustainability at the landscape scale. Much of Dr. Travis’s work stems from his studies of reproduction and the function and preservation of sperm. His lab announced the birth of the world's first litter of puppies born by in vitro fertilization in December, 2015.

In one recent success in assisted reproduction, the Travis lab was the first group in the Western Hemisphere to successfully perform embryo transfer using a frozen dog embryo. They also claim the title of first to successfully perform spermatogonial stem cell transplantation in a dog, a procedure in which the sperm-making stem cells from the testes of one dog are transferred into another dog. After the procedure, the recipient dog is capable of creating sperm that carry the donor dog’s genetic material. By trying new techniques for assisting reproduction in dogs, Dr. Travis and his colleagues expect to learn more about how these approaches might be used to aid reproduction in humans and in non-domesticated species that are closer to extinction, including rare wolf species.

In other work related to reproduction, the Travis lab is exploring the interactions between the various components of the outer membrane of sperm that enable them to carry out their one objective: fusing with an egg cell and creating an embryo. One component, the ganglioside GM1, is under particular scrutiny. They have demonstrated that GM1 regulates a channel that allows calcium into the sperm, a critical first step that enables a sperm to fertilize an egg. Dr. Travis is applying these findings in a new assay, now in human clinical trials, that analyzes the distribution of GM1 in the sperm membrane as a way of diagnosing male fertility.

Sperm are interesting because of their role in reproduction, but the Travis lab is also putting components of the long sperm tail to work for different purposes. Building on their past studies of sperm’s energy-making enzymes, Dr. Travis and his colleagues are working to mimic the way these enzymes are organized in the tail, called a “flagellum”, to create enzyme machines powered by sugar. These tiny powerhouses could eventually be integrated into implanted hybrid biological/mechanical medical devices, where they would run on the sugars available in a patient's bloodstream. Although those applications sound like science fiction, there are also more immediate uses for these tethered enzymes. For example, the Travis lab is exploring how enzymes attached to nanoparticles could be used as the basis for hand-held devices that could diagnose strokes or traumatic brain injuries within just a few minutes.

Dr. Travis’s interest in biology extends beyond cell and molecular studies into wildlife and landscape-scale approaches to conservation, work that calls on his veterinary training. As the Faculty Director for the Environment at Cornell's Atkinson Center for a Sustainable Future and the Director of the Cornell Center for Wildlife Conservation, Dr. Travis collaborates with researchers from around Cornell and the world to study large-scale interventions aimed at conserving wildlife and fighting human poverty and hunger by promoting sustainable agriculture and natural resource management. In one ongoing project, Dr. Travis's lab is collaborating with the non-profit business COMACO to develop egg layer facilities in remote rural communities in Zambia that will make chicken eggs more available in an area with persistent poverty and hunger. Over 50% of the children in this area show signs of chronic malnourishment and families have historically relied on bushmeat when they did not have enough food. One of Dr. Travis's students is measuring the impacts that local egg production might have on the health and nutrition of mothers and children, while simultaneously relieving pressure on wildlife.

Select Publications:

  1. Nagashima JB, Sylvester SR, Nelson JL, Cheong SH, Mukai C, Lambo C, et al. (2015) Live Births from Domestic Dog (Canis familiaris) Embryos Produced by In Vitro Fertilization. PLOS One, 10(12): e0143930.

  2. Cohen R, Buttke DE, Asano A, Nelson JL, Ren D, Miller R, Cohen-Kutner M, Atlas D, and Travis AJ. (2014) Lipid modulation of calcium flux through CaV2.3 regulates acrosome exocytosis and fertilization. Developmental Cell, 28:310-321. Abstract.

  3. Gao L, Giglio KM, Nelson JL, Sondermann H, and Travis AJ. (2014) Ferromagnetic nanoparticles with peroxidase-like activity enhance the cleavage of biological macromolecules for biofilm elimination. Nanoscale, 6:2588-2593.

  4. Kim B, Zhang X, Kan R, Cohen R, Mukai C, Travis AJ, and Coonrod, S.A. (2014) The role of MATER in endoplasmic reticulum distribution and calcium homeostasis in mouse oocytes. Developmental Biology, 386:331-339. Abstract.

  5. Asano A, Nelson-Harrington JL, Travis AJ. (2013). Phospholipase B is activated in response to sterol removal and stimulates acrosome exocytosis in murine sperm. Journal of Biological Chemistry, 27;288(39):28104-15. Abstract.

  6. Kiso, Wendy K.; Selvaraj, Vimal; Nagashima, Jennifer; Asano, Atsushi; Brown, Janine L.; Schmitt, Dennis L.; Leszyk, John; Travis, Alexander J.; Pukazhenthi, Budhan S.. 2013). Lactotransferrin in Asian Elephant (Elephas maximus) Seminal Plasma Correlates with Semen Quality. PLOS One, Vol. 8 Issue 8, p1.

  7. Harkey MA, Asano A, Zoulas ME, Torok-Storb B, Nagashima J, Travis A. (2013). Isolation, genetic manipulation, and transplantation of canine spermatogonial stem cells: progress toward transgenesis through the male germ-line. Reproduction, 14;146(1):75-90. Abstract.

  8. Mukai C, Gao L, Bergkvist M, Nelson JL, Hinchman MM, Travis AJ. (2013). Biomimicry enhances sequential reactions of tethered glycolytic enzymes, TPI and GAPDHS. PLOS One, 23;8(4):e61434.

  9. Kiso WK, Asano A, Travis AJ, Schmitt DL, Brown JL, Pukazhenthi BS. (2012). Pretreatment of Asian elephant (Elephas maximus) spermatozoa with cholesterol-loaded cyclodextrins and glycerol addition at 4°C improves cryosurvival. Reproduction Fertility and Development, 24(8):1134-42. Abstract.

  10. Barrett CB, Travis AJ, Dasgupta P. (2011). On biodiversity conservation and poverty traps. Proceedings of the National Academy of Sciences, 23;108(34):13907-12. Abstract.

  11. Lewis D, Bell, SD, Fay, J, Both KL, Gatere, L, Kabila M, Mukamba M, Matokwani E,  Mushimbalume M, Moraru CI, Lehmann J, Lassoie J, Wolfe D, Lee DR, Buck L, Travis AJ. (2011). Community Markets for Conservation (COMACO) links biodiversity conservation with sustainable improvements in livelihoods and food production. Proceedings of the National Academy of Sciences, 23;108(34):13957–13962. Abstract. *This article was chosen to provide the cover image for the issue, and was selected for Faculty of 1000 Prime (F1000P).

  12. Gourdon JC, Travis AJ. (2011). Spermatogenesis in ferret testis xenografts: a new model. Comparative Medicine, 61(2):145-9. Abstract.

  13. Selvaraj V, Asano A, Page JL, Nelson JL, Kothapalli KS, Foster JA, Brenna JT, Weiss RS, Travis AJ. (2010). Mice lacking FABP9/PERF15 develop sperm head abnormalities but are fertile. Developmental Biology, 348(2):177-89. Abstract.

  14. Asano A, Nelson JL, Zhang S, Travis AJ. (2010). Characterization of the proteomes associating with three distinct membrane raft sub-types in murine sperm. Proteomics, 10(19):3494-505. Abstract.

  15. Mukai C, Bergkvist M, Nelson JL, Travis AJ. (2009). Sequential reactions of surface- tethered glycolytic enzymes. Chemistry and Biology, 16(9):1013-20. Abstract. *Featured Article (see also Hess, H. Reassembling biological machinery in vitro, Chemistry and Biology 16:917-918. Abstract.)

  16. Kim Y, Turner D, Nelson JL, Dobrinski I, McEntee M, and Travis AJ.  (2008).  Production of donor-derived sperm after spermatogonial stem cell transplantation in the dog. Reproduction 136:823-831. Abstract.

Links and abstracts for all of Dr. Travis’s publications can be found at PubMed.