Opening Address of the 28th Conference of European Comparative Endocrinologists, CECE, at Leuven, Belgium on August 21, 2016
By Horst-Werner Korf, President of the European Society for Comparative Endocrinology (ESCE). Dr. Senckenbergische Anatomie und Dr. Senckenbergisches Chronomedizinisches Institut, Faculty of Medicine, Goethe University, Frankfurt am Main, Germany.
Professor Torfs, Professor Vanden Broeck, dear Jef, dear colleagues and members of the ESCE,
First of all I would like to thank you Prof. Torfs, on behalf of the ESCE, very much for your warm and kind words of welcome, we feel honored and very much appreciate the presence of the Rector magnificus of the Katholieke Universiteit of Leuven at the opening ceremony of the 28th CECE. We are grateful that this traditional and famous university hosts and supports our biannual congress. The 28th CECE comprises a rich and very exciting program covering nearly all major themes of comparative endocrinology and will be a forum allowing all participants to present and discuss new results, ideas and concepts. It is not the first time that a CECE is held in Leuven, 26 years ago the 15th CECE was already organized in this marvellous and picturesque city by our highly distinguished colleague Arnold de Loof and his team. Arnold, we cordially welcome you and thank you for your long lasting service to the ESCE, as secretary treasurer (1983-1989), as vice president (1990-1994), as president (1994) and actually as Honorary President.
CECEs have a long lasting tradition, the actual conference forms the tip of an impressive row of meetings starting with the first conference in London in 1963, which, I would guess, has been attended only by very few, if any of us. However, I see several colleagues who have attended and even organized the more recent CECEs. A warm welcome to Dan Larhammar, who organized the 22nd CECE in Uppsala in 2004 and who has served the ESCE as vice president (2006-2010) and president (2010- 2014) and to Elisabeth Eppler, who organized the 26th CECE 2012 in Zürich and keeps the books of the ESCE as secretary treasurer since 2010.
It was the CECE which gave birth to the ESCE: During the third CECE in Copenhagen several eminent colleagues, for example Hans Heller of Bristol, Manfred Gersch of Jena, Maurice Fontaine of Paris, Ernest Barrington of Nottingham, Valdo Mazzi of Torino and Gregorius van Oordt of Utrecht “decided to establish an international forum for scientists” (i.e. the ESCE) “ interested in biological, chemical, medical and veterinary aspects of the endocrine system, and to organize biannual meetings in European centres for comparative endocrinology” (P.G.W.J. Van Oordt, 1987). They realized that such meetings “would lead to mutual appreciation and cooperation among those studying various aspects of comparative endocrinology in Europe, and in doing so, would not only promote this field of science but would also further international understanding in general” (P.G.W.J. Van Oordt, 1987).
In serving these goals the ESCE has grown up, it left the stages of childhood, puberty, young adulthood and has reached, believe it or not, the age of 50. At this (st)age humans as well as societies got different options for development: on the one hand they may feel quite old already, enter midlife crisis, change gears and leave back nearly everything what is behind them. On the other hand they may feel mature and rather secure, but not old; they may realize the accomplishments (and also the mistakes!) over the last five decades with some satisfaction and prepare for the future on the basis of the past, get new ideas and set out for the next decades to come. We all hope that the ESCE will take the latter option and we all should and shall work hard for this.
Our young colleagues, the PhD students and postdocs are the ones who will carry on the torch. To underline this important role, the ESCE has founded on the occasion of its 50th anniversary the ESCE Young Investigator Award that will be for the first time bestowed upon colleagues under the age of 35 who will deliver the best oral and the best poster presentations to the 28th CECE. So watch out who is sitting in your session or who is asking nasty questions about your oral communication or about your poster. One or two of those questioners may belong to the prize committee.
But let us now turn to the question whether the scientific goals of the ESCE have still some value in our modern times in which we tend to undertake a certain kind of reductionism and we have to ask ourselves whether “single species” endocrinology, i.e., endocrinology of a single species (be it fish or human, mouse or Drosophila) is more appropriate and more timely than endocrinology comparing different species, i.e., comparative endocrinology.
I shall try to answer this question by shortly presenting three examples which, I must admit, are selected from a very subjective perspective, because they relate to my own research interests.
In my opinion one the most shining examples for the value of comparative endocrinology is the foundation and development of the concept of neurosecretion and neuroendocrinology stating that neurons not only generate action potentials, but are also capable of producing and secreting hormones into body fluids. This concept has been developed by Ernst and Berta Scharrer in the 1930s while, and I apologize for the regionalism, they worked in the Ludwig Edinger Institute in Frankfurt am Main. In these early days the concept was heavily defeated by several eminent neurophysiologists and neuroanatomists, the findings of the Scharrers were considered staining artefacts and the final breakthrough became only possible because the Scharrers did not restrict themselves to one or two species but investigated the whole animal kingdom from worms, molluscs and arthropods to cyclostomes, fish, amphibians, reptiles, birds and mammals including man. (Image left: Biol. Rev. 12:185-216, 1937)
Ernst and Berta Scharrer
Another important example for the value of comparative endocrinology is the discovery of the molecular clockwork that underlies the circadian system which controls endocrine rhythms in virtually all species including man. In principle the clockwork comprises clock genes which interact in transcriptional/translational feedback loops and encode for inhibiting and activating transcription factors. The first clock genes were identified in Drosophila by Konopka and Benzer 1971 and the Drosophila per gene was sequenced in 1984 by Michael Rosbash and his team, and these results from Drosophila paved the way for the discovery of the homologous genes in mammals (i.e. mouse) by the groups of Jo Takahashi, Hitoshi Okamura and Steve Reppert in the 1990s.
Notably, the endogenous circadian clock needs to be synchronized by environmental cues which, according to Jürgen Aschoff, are called Zeitgebers. The photoperiod, i.e., the daily change of light and darkness is one of the most important zeitgeber entraining the circadian system. That light stimuli not only serve the image formation, but also the control of the endocrine system has already been realized in the 1920ies by Karl von Frisch and in 1964 his disciple, Ernst Scharrer introduced his concept on photoneuroendocrine systems which translate light stimuli into hormonal responses and thus serve the orientation in time rather than serving the orientation in space via image formation.
The search for these non-image forming, circadian photoreceptors has a long history; in non- mammalian species, the pineal organ has been identified as one brain area where such photoreceptors are located. Andreas Oksche of Giessen, my scientific master, who organized the 9th CECE in Giessen in 1977 and who served as ESCE president from 1973 to 1977 has made seminal contributions to pineal photoreceptors by virtue of his fundamental comparative investigations.
Andreas Oksche
In the late 1980s the efforts to identify such circadian photoreceptors have revealed stunning results, once again based on comparative studies. Who in those days would be interested in the phototransduction cascade of a cell that occurs only at a certain stage of development in species that are of no applied value? Which organization would provide funds for such type of studies? It has been my good old colleague and friend Mark Rollag of Bethesda who was interested in the phototransduction cascade of directly photosensitive melanophores present in the tail fin of Xenopus tadpoles and he pursued his research with constant focus and, in the beginning, with very little, if any funding. His studies paid off and he and his group discovered a novel photopigment, which because of its discovery in the the tail fin melanophores is called melanopsin. Unexpectedly this discovery in tail fin melanophores has proven to be of general and applied importance. It is the photopigment which provides the Zeitgeber for entraining the circadian clock, it is the photopigment of the novel circadian photoreceptors extensively studied by Russell Foster which are located in the ganglion cell layer of the retina of mammals and man. It is responsible for the fact that blue light at night disrupts the circadian rhythm and is unhealthy for man and mammals.
I hope that with these three examples I could reinforce your enthusiasm for comparative endocrinology and stimulate your appetite for the 28th CECE. We are extremely grateful to our highly respected colleague Jozef (Jef) Vanden Broeck who has taken the burden to organize this conference and who has put together an exciting and multifaceted program. Thank you, Jef, and your team for all your efforts!
And with this I declare the 28th CECE in Leuven open.
Have a stimulating meeting with many stimulating interactions and discussions.
Professor Torfs, Professor Vanden Broeck, dear Jef, dear colleagues and members of the ESCE,
First of all I would like to thank you Prof. Torfs, on behalf of the ESCE, very much for your warm and kind words of welcome, we feel honored and very much appreciate the presence of the Rector magnificus of the Katholieke Universiteit of Leuven at the opening ceremony of the 28th CECE. We are grateful that this traditional and famous university hosts and supports our biannual congress. The 28th CECE comprises a rich and very exciting program covering nearly all major themes of comparative endocrinology and will be a forum allowing all participants to present and discuss new results, ideas and concepts. It is not the first time that a CECE is held in Leuven, 26 years ago the 15th CECE was already organized in this marvellous and picturesque city by our highly distinguished colleague Arnold de Loof and his team. Arnold, we cordially welcome you and thank you for your long lasting service to the ESCE, as secretary treasurer (1983-1989), as vice president (1990-1994), as president (1994) and actually as Honorary President.
CECEs have a long lasting tradition, the actual conference forms the tip of an impressive row of meetings starting with the first conference in London in 1963, which, I would guess, has been attended only by very few, if any of us. However, I see several colleagues who have attended and even organized the more recent CECEs. A warm welcome to Dan Larhammar, who organized the 22nd CECE in Uppsala in 2004 and who has served the ESCE as vice president (2006-2010) and president (2010- 2014) and to Elisabeth Eppler, who organized the 26th CECE 2012 in Zürich and keeps the books of the ESCE as secretary treasurer since 2010.
It was the CECE which gave birth to the ESCE: During the third CECE in Copenhagen several eminent colleagues, for example Hans Heller of Bristol, Manfred Gersch of Jena, Maurice Fontaine of Paris, Ernest Barrington of Nottingham, Valdo Mazzi of Torino and Gregorius van Oordt of Utrecht “decided to establish an international forum for scientists” (i.e. the ESCE) “ interested in biological, chemical, medical and veterinary aspects of the endocrine system, and to organize biannual meetings in European centres for comparative endocrinology” (P.G.W.J. Van Oordt, 1987). They realized that such meetings “would lead to mutual appreciation and cooperation among those studying various aspects of comparative endocrinology in Europe, and in doing so, would not only promote this field of science but would also further international understanding in general” (P.G.W.J. Van Oordt, 1987).
Our young colleagues, the PhD students and postdocs are the ones who will carry on the torch. To underline this important role, the ESCE has founded on the occasion of its 50th anniversary the ESCE Young Investigator Award that will be for the first time bestowed upon colleagues under the age of 35 who will deliver the best oral and the best poster presentations to the 28th CECE. So watch out who is sitting in your session or who is asking nasty questions about your oral communication or about your poster. One or two of those questioners may belong to the prize committee.
But let us now turn to the question whether the scientific goals of the ESCE have still some value in our modern times in which we tend to undertake a certain kind of reductionism and we have to ask ourselves whether “single species” endocrinology, i.e., endocrinology of a single species (be it fish or human, mouse or Drosophila) is more appropriate and more timely than endocrinology comparing different species, i.e., comparative endocrinology.
I shall try to answer this question by shortly presenting three examples which, I must admit, are selected from a very subjective perspective, because they relate to my own research interests.
Ernst and Berta Scharrer
Another important example for the value of comparative endocrinology is the discovery of the molecular clockwork that underlies the circadian system which controls endocrine rhythms in virtually all species including man. In principle the clockwork comprises clock genes which interact in transcriptional/translational feedback loops and encode for inhibiting and activating transcription factors. The first clock genes were identified in Drosophila by Konopka and Benzer 1971 and the Drosophila per gene was sequenced in 1984 by Michael Rosbash and his team, and these results from Drosophila paved the way for the discovery of the homologous genes in mammals (i.e. mouse) by the groups of Jo Takahashi, Hitoshi Okamura and Steve Reppert in the 1990s.
The search for these non-image forming, circadian photoreceptors has a long history; in non- mammalian species, the pineal organ has been identified as one brain area where such photoreceptors are located. Andreas Oksche of Giessen, my scientific master, who organized the 9th CECE in Giessen in 1977 and who served as ESCE president from 1973 to 1977 has made seminal contributions to pineal photoreceptors by virtue of his fundamental comparative investigations.
Andreas OkscheIn the late 1980s the efforts to identify such circadian photoreceptors have revealed stunning results, once again based on comparative studies. Who in those days would be interested in the phototransduction cascade of a cell that occurs only at a certain stage of development in species that are of no applied value? Which organization would provide funds for such type of studies? It has been my good old colleague and friend Mark Rollag of Bethesda who was interested in the phototransduction cascade of directly photosensitive melanophores present in the tail fin of Xenopus tadpoles and he pursued his research with constant focus and, in the beginning, with very little, if any funding. His studies paid off and he and his group discovered a novel photopigment, which because of its discovery in the the tail fin melanophores is called melanopsin. Unexpectedly this discovery in tail fin melanophores has proven to be of general and applied importance. It is the photopigment which provides the Zeitgeber for entraining the circadian clock, it is the photopigment of the novel circadian photoreceptors extensively studied by Russell Foster which are located in the ganglion cell layer of the retina of mammals and man. It is responsible for the fact that blue light at night disrupts the circadian rhythm and is unhealthy for man and mammals.
I hope that with these three examples I could reinforce your enthusiasm for comparative endocrinology and stimulate your appetite for the 28th CECE. We are extremely grateful to our highly respected colleague Jozef (Jef) Vanden Broeck who has taken the burden to organize this conference and who has put together an exciting and multifaceted program. Thank you, Jef, and your team for all your efforts!
And with this I declare the 28th CECE in Leuven open.
Have a stimulating meeting with many stimulating interactions and discussions.