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In Memoriam - Volker Schmid (1939-2008)

Authors:
Walter J Gehring at University of Basel
Walter J Gehring
Brigitte Galliot at University of Geneva
Brigitte Galliot
Stefano Piraino at University of Salento
Stefano Piraino
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Abstract

Volker Schmid died peacefully on April 1, 2008, after a long severe illness. We have lost an outstanding developmental biologist who made some most important contributions to the field of cell transdifferentiation and the evolutionary developmental biology of cnidarians. Volker Schmid was born on September 23, 1939 at Schweidnitz (Poland), at the beginning of World War II. His father was a German engineer, his mother was Swiss. In the winter of 1945, Volkers family fled to Germany and later to Switzerland. He was a gifted student and entered the University of Zurich to study his favorite topic, zoology. At that time,....
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in Zurich for another three years as an assistant, continuing his research on the gametogenesis and regeneration of Hydrozoa, and
teaching medical students. For his postdoctoral training he wanted to familiarize himself with the modern techniques of molecular
biology. Therefore in 1975 he joined Arthur Whitely at the University of Washington in Seattle. Most of the time he worked at the marine
station of Friday Harbor on San Juan Island where, before returning to Zurich, Volker and Käthi bought a cottage right on the seashore
where, since then, they returned almost every year to spend their summer vacations.
In 1978, Volker Schmid got his habilitation as Privatdozent in Zurich, and in 1981, he was nominated Extraordinarius at the Zoological
Institute of the University of Basel, where he was later promoted to Ordinarius (full professor). A breakthrough in his scientific career
came from his work with a hydrozoan jellyfish, Podocoryne carnea. Schmid demonstrated that the mononucleated striated muscle cells of
these tiny medusae provide a unique model system in the animal kingdom to study cell transdifferentiation. In the animal and under
defined culture conditions these cells seem to be terminally committed and they do not divide anymore. After destabilisation, however,
the cells start to transdifferentiate into smooth muscle cells and resume cell division. In an asymmetric stem cell-like manner, smooth
muscle cells divide into a further dividing smooth muscle cell and a non-dividing, terminally differentiated nerve cell. Eventually, new
organs are formed as if the muscle cells try to regenerate a whole animal. When he shot a picture containing both cross-striated muscle
fibres and a nematocyst in the same cell, even his most vivid critics became convinced that cross-striated muscle cells can transdifferentiate
into other cell types. His findings were published in the journal “Cell”. The transdifferentiation studies made by Volker Schmid were
particularly appreciated in Japan, where he was repeatedly invited to give seminars. Recently, genetically reprogrammed, induced
pluripotent stem cells have become a popular topic. Volker Schmid was actually among the few scientists who identified and documented
a striking case of cell plasticity, i.e. the reprogramming of differentiated somatic cells to pluripotent progenitors. In the following years,
with several members of his laboratory he carefully investigated the role of structural and regulatory genes in the complex jellyfish life
cycle and in transdifferentiation, providing milestone contributions in the cnidarian evo-devo literature.
Working on the striated muscle layer of hydrozoans had another equally important outcome. Volker Schmid offered rigorous,
undisputed arguments towards the occurrence of mesodermal anatomies in all cnidarians classes and the conservation of a common
regulatory gene cascade for the myogenic lineage differentiation between cnidarians and Bilateria, pointing to the Urtriploblast as a
common triploblast ancestor. More recently, he discovered some non-radially organized hydrozoan larvae, with an anterior concentration
of sensory and ganglionic nerve elements, suggesting that a fundamental genetic toolkit for the establishment of bilateral and polarized
Volker Schmid died peacefully on April 1, 2008, after a long severe illness. We have
lost an outstanding developmental biologist who made some most important
contributions to the field of cell transdifferentiation and the evolutionary
developmental biology of cnidarians.
Volker Schmid was born on September 23, 1939 at Schweidnitz (Poland), at the
beginning of World War II. His father was a German engineer, his mother was Swiss.
In the winter of 1945, Volker’s family fled to Germany and later to Switzerland. He
was a gifted student and entered the University of Zurich to study his favorite topic,
zoology.
At that time, the Zoological Institute was headed by Ernst Hadorn, who had an
excellent reputation both as an experimental developmental biologist and a
teacher. Together with Jean Brachet and Paul Weiss, Hadorn had founded the new
journal of “Developmental Biology” which combined embryology with biochemistry
and cell biology into a new discipline called developmental biology. Therefore,
Volker Schmid was exposed to a profound and broad education in biology. Hadorn
also taught a marine biology course in Banyuls (Southern France), which elicited
Volker Schmid’s interest in the ontogeny of marine organisms. He did his Ph.D.
thesis under the guidance of Pierre Tardent, who had retuned to Switzerland after
many years of work at the Stazione Zoologica “Anton Dohrn” in Naples. Pierre
Tardent introduced Volker to jellyfish development, which remained Volker’s
favourite research topic for the rest of his life.
In 1962, Volker married Käthi Mattenberger, a student of natural sciences in
Zurich, and together they had four children: Gisele (who died on the second day
of her life), Lonja, Mark and Jan. After getting his Ph.D., Volker Schmid stayed on
THE INTERNATIONAL JOURNAL OF
DEVELOPMENTAL
BIOLOGY
www.intjdevbiol.com
IN MEMORIAM
Int. J. Dev. Biol. 52: 1013-1014 (2008)
doi: 10.1387/ijdb.082708wg
Volker Schmid (1939 - 2008)
anatomies was already present before the Cnidaria-Bilateria divergence. However, he was not given enough time to complete this work,
and it will be up to his students and colleagues to settle these problems.
After his official retirement in 2005, he did not interrupt his scientific and educational activities. Indeed, Volker was also an enthusiastic
teacher. For many years, he regularly organized and chaired courses on the experimental developmental biology of marine invertebrates
in field stations, especially at the Station Biologique in Roscoff, attended by students from all Europe. Roscoff was one of the favorite
research stations of Volker Schmid and he left there many friends to whom he conveyed passion and joy for research. Since 2008, the
Roscoff course appears under his name, and will continue in the future years as The Volker Schmid Training Course.
With Volker Schmid's passing away, we have lost a great scientist and zoologist, a warm and friendly person, loving his experimental work
and Nature in all forms. Volker was not just a dedicated scientist, but also a naturalist, a tenacious mushroom hunter, and a renowned
fisherman, particularly for salmon. Many times he created a serious problem for the customs officers at Friday Harbor, when he arrived
with some large empty suitcases. He needed those to take back some 50 pounds of frozen salmon when leaving for Switzerland! We have
had the privilege to meet him and share with him work and good times. We shall keep our best memories of him, not only as an excellent
and acute scientist, but also as a man of fine and exquisite personality.
Walter Gehring, Brigitte Galliot and Stefano Piraino
Basel, Geneva and Lecce, June 2008
Address correspondance to: Stefano Piraino. DISTEBA, Università del Salento, 73100 Lecce, Italy.
e-mail: stefano.piraino@unile.it Tel./fax ++39-0832-298-616
Selected References
SCHMID, V. (1976). The transformational potential of striated muscle in hydromedusae.
Dev Biol
. 49: 508-17.
SCHMID, V., WYDLER, M. and ALDER, H. (1982). Transdifferentiation and regeneration in vitro.
Dev Biol.
92: 476-88.
SCHMID, V. and ALDER, H. (1984). Isolated, mononucleated, striated muscle can undergo pluripotent transdifferentiation and form a complex regenerate.
Cell
. 38: 801-809.
SCHMID, V. and PLICKERT, G. (1990). The proportion altering factor (PAF) and the in vitro transdifferentiation of isolated striated muscle of jellyfish into nerve cells.
Differentiation
. 44: 95-102.
SCHMID, V. (1992). Transdifferentiation in Medusae.
Int. Rev. Cytology
. 142: 213-261.
SCHMID, V., AESCHBACH, B., AGATA, K., KOSAKA, J., REBER-MÜLLER, S., SPRENGER, N. AND EGUCHI, G. (1995). Cell adhesion to extracellular matrix is different
in marine hydrozoans compared with vertebrates.
Roux’s Arch. Dev. Biol
. 204: 465-476.
AERNE, B.L., BAADER, C.D. and SCHMID, V. (1995). Life stage and tissue-specific expression of the homeobox gene cnox1-Pc of the hydrozoan Podocoryne carnea.
Dev
Biol.
169: 547-56.
REBER-MÜLLER, S., SPISSINGER, T., SCHUCHERT, P., SPRING, J. and SCHMID, V. (1995). An extracellular matrix protein of jellyfish homologous to mammalian fibrillins
forms different fibrils depending on the life stage of the animal.
Dev Biol.
169: 662-72.
PIRAINO, S., BOERO, F., AESCHBACH, B. and SCHMID, V. (1996). Reversing the life cycle: Medusae transforming into polyps and cell transdifferentiation in
Turritopsis
nutricula
(Cnidaria, Hydrozoa).
Biol Bull
.
Woods Hole
190: 302-12.
YANZE, N., GRÖGER, H., MÜLLER, P. and SCHMID, V. (1999). Reversible inactivation of cell-type-specific regulatory and structural genes in migrating isolated striated muscle
cells of jellyfish.
Dev Biol
. 213: 194-201.
MÜLLER, P., YANZE, N., SCHMID, V. and SPRING, J. (1999). The homeobox gene Otx of the jellyfish Podocoryne carnea: role of a head gene in striated muscle and evolution.
Dev Biol
. 216: 582-94.
SPRING, J., YANZE, N., MIDDEL, A.M., STIERWALD, M., GRÖGER, H. and SCHMID, V. (2000). The Mesoderm Specification Factor Twist in the Life Cycle of Jellyfish.
Dev
Biol.
228: 363-75.
GRÖGER, H. and SCHMID, V. (2001). Larval development in Cnidaria: A connection to bilateria?
Genesis
. 29: 110-114.
YANZE, N., SPRING, J., SCHMIDLI, C. and SCHMID, V. (2001). Conservation of Hox/ParaHox-related genes in the early development of a cnidarian.
Dev Biol.
236: 89-98.
GALLIOT, B. and SCHMID, V. (2002). Cnidarians as a model system for understanding evolution and regeneration.
Int J Dev Biol.
46: 39-48.
SPRING, J., YANZE, N., JÖSCH, C., MIDDEL, A.M., WINNINGER, B. and SCHMID, V. (2002). Conservation of Brachyury, Mef2 and Snail in the myogenic lineage of jellyfish:
A connection to the mesoderm of Bilateria.
Dev Biol.
244: 372-84.
MÜLLER, M., SEIPEL, K., REBER-MÜLLER, S., STREITWOLF-ENGEL, R., STIERWALD, M., SPRING, J. and SCHMID, V. (2003). Evolutionary aspects of developmentally
regulated helix-loop-helix-transcription factors in striated muscle of jellyfish.
Dev. Biol.
255: 216-229.
STIERWALD, M., YANZE, N., BAMERT, R., KAMMERMEIER, L. and SCHMID, V. (2004). The Sine oculis/Six class family of homeobox genes in jellyfish with and without
eyes:Development and eye regeneration.
Dev Biol. 2
74: 70-81.
SEIPEL, K., YANZE, N. and SCHMID, V. (2004). The germ line and somatic stem cell gene Cniwi in the jellyfish Podocoryne carnea.
Int. J. Dev. Biol.
48: 1-7.
SEIPEL, K., EBERHARDT, M., MÜLLER, P., PESCIA, E., YANZE, N. and SCHMID, V. (2004). Homologs of vascular endothelial growth factor and receptor, VEGF and VEGFR,
in the jellyfish Podocoryne carnea.
Dev Dyn.
231: 303-312.
SEIPEL, K., SCHMID, V. (2005). Evolution of striated muscle: jellyfish and the origin of triploblasty.
Dev Biol.
282: 14-26.
REBER-MÜLLER, S., STREITWOLF-ENGEL, R., YANZE, N., SCHMID, V., STIERWALD, M., ERB, M. AND SEIPEL, K. (2006). BMP2/4 and BMP5-8 in jellyfish development
and transdifferentiation
Int. J. Dev. Biol.
50: 377-384.
SEIPEL, K., SCHMID, V. (2006). Mesodermal anatomies in cnidarian polyps and medusae.
Int J Dev Biol
. 50: 589-99.
IN MEMORIAM
... zoologist Volker Schmid, who was an iconic teacher for the course, and who passed away in 2008 [1] . 40 ...
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