MiniBio: Omar Trujillo Cenoz is currently an Emeritus Professor at the department of Cellular and Molecular Neurophysiology at Instituto Clemente Estable. He was head of the Neuroanatomy department at Instituto Clemente Estable from 1973 to 2004, and retired in 2004. He studied under the guidance of Prof. Clemente Estable in Montevideo, Uruguay, and later completed further studies at UCLA, in the lab of Prof. Fritiof Sjöstrand. His expertise spans optical and electron microscopy over several decades.
What inspired you to become a scientist?
Since I was a child I was attracted by animals and their behaviors. Later education (primary school, secondary, etc) reinforced this initial vocation. Finally, my first contacts with Professor Clemente Estable (concerned with a peculiar arachnid species) strengthened my decision to dig into the field of biological sciences.
You have a career-long involvement in microscopy and neurosciences. What inspired you to choose this career path?
My first contact with Prof. Estable (who was one of Prof. Ramón y Cajal’s students) directed my attention to the nervous system and the problems posed by neuronal connectivity. I believe that these early contacts biased my career path towards neuroscience.
Can you tell us a bit about what you have found uniquely positive about becoming a researcher in Uruguay, from your education years?
My pioneer relationship with Prof. Estable and other members of his research team demonstrated that it was possible to acquire knowledge and neuro-histological abilities in Uruguay, paralleling the routine academic studies.
Can you tell us a bit about your general research path, and how this shaped you as a microscopist both at home and abroad?
I started studying medicine in Montevideo (State University). Fortunately I won a fellowship to join the Instituto de Ciencias Biológicas (then directed by Prof. Estable). Estable and his colleagues at the Institute were very well trained for using Cajal’s reduced silver and Golgi techniques to stain nervous tissue. Moreover, the institute hosted an electron microscope (EM) manipulated by Dr. Eduardo De Robertis, who together with Dr. J.R. Sotelo, taught me how to operate the instrument. They also taught me how to prepares nervous tissues to obtain ultrathin sections for EM visualization and analysis. I received complementary teaching to deal with serial sectioning and 3D EM reconstructions during my fellowship in UCLA ( Sjöstrand´s laboratory).
Did you have many opportunities to interact with other Latin American groups, outside of Uruguay?
No, during this first period of my scientific career I had no contacts with Latin- American scientists.
Having worked abroad, what were some of the things you found to be very different between doing research in Uruguay, and abroad?
In general, the main differences were (and still are) linked to considerable budget availabily and facilities (which often possess better financing abroad), that in turn, are linked with very well equipped laboratories. In addition, scientific communication between dissimilar disciplines has greatly improved, resulting in greater interdisciplinary science.
Have you ever faced any specific challenges as a Uruguayan researcher, working abroad?
When abroad I never had to deal with unpleasant behaviors or discriminatory challenges.
Who are your scientific role models (both Uruguayan and foreign)?
Role models in Uruguay: Clemente Estable, José Pedro Segundo.
Role models abroad : T.H Bullock , Fritiof Sjöstrand
What is your opinion on gender balance in Uruguay, given current initiatives in the country to address this important issue. How has this impacted your career?
I believe that Uruguay is relatively well balanced. This never interfered with my career.
What is your favourite type of microscopy and why?
I used mostly electron-microscopy techniques combined with immunocytochemistry. Therefore I enjoy and appreciate the high resolution offered by a well maintained electron microscope. On the other hand confocal microscopes (Zeiss or Olympus) are able to provide excellent complementary images. Both are fine instruments with high quality optics. I have no experience with the recently developed photonic microscopes with greatly increased resolution allowing in vivo visualization of cell components (synaptic vesicles, for example).
What is the most extraordinary thing you have seen by microscopy? An eureka moment for you?
My “eureka moment” was when I was able to reveal (using serial sectioning EM) the connectivity laws commanding the functional links between the photoreceptors and the second order neurons in the retina of dipterans.
What is an important piece of advice you would give to future Uruguayan scientists? and especially those specializing as microscopists?
I strongly recommend to acquire in-depth knowledge of and become familiar with physics, particularly optics.
Where do you see the future of science and microscopy heading over the next decade in Uruguay, and how do you hope to be part of this future?
I cannot be very optimistic about the future. Even after the evidence collected during the recent COVID pandemic assault, politicians remain reluctant to finance basic research. However, I am 89 years old and therefore the word “future” is, resulting from biological laws, a short period.
Beyond science, what do you think makes Uruguay a special place to visit and go to as a scientist?
Uruguay is a nice place to live. However, it remains very difficult to obtain funds to finance basic research (percentage of the national budget devoted to scientific research is below 0.5%).