Hans Ris (June 15, 1914 – November 19, 2004) was an American cytologist and pioneer electron microscopist. His studies of

chromosome structure Eukaryotic chromosome structure refers to the levels of packaging from raw DNA molecules to the chromosomal structures seen during metaphase in mitosis or meiosis. Chromosomes contain long strands of DNA containing genetic information. Compared to ...

revealed the importance of non-histone proteins, and along with evolutionary biologist Lynn Margulis, he was one of the first to recognize that blue-green algae were a special type of bacteria. He coined the term

genophore The nucleoid (meaning ''nucleus-like'') is an irregularly shaped region within the prokaryotic cell that contains all or most of the genetic material. The chromosome of a prokaryote is circular, and its length is very large compared to the cell dim ...

for prokaryote DNA to highlight its differences from the eukaryal chromosome. Ris was a founding member of the American Society for Cell Biology and received the Distinguished Scientist Award by the

Microscopy Society of America The Microscopy Society of America (MSA) was founded in 1942 as The Electron Microscope Society of America and is a non-profit organization that provides microanalytical facilities for studies within the sciences. Currently, there are approximately 3 ...

in 1983.

Biography

Hans Ris was born in

Bern german: Berner(in)french: Bernois(e) it, bernese , neighboring_municipalities = Bremgarten bei Bern, Frauenkappelen, Ittigen, Kirchlindach, Köniz, Mühleberg, Muri bei Bern, Neuenegg, Ostermundigen, Wohlen bei Bern, Zollikofen , website ...

, Switzerland on 15 June 1914, where he also grew up. Inspired by the works of the French

entomologist Entomology () is the scientific study of insects, a branch of zoology. In the past the term "insect" was less specific, and historically the definition of entomology would also include the study of animals in other arthropod groups, such as arach ...

Jean Henri Fabre Jean-Henri Casimir Fabre (21 December 1823 – 11 October 1915) was a French naturalist, entomologist, and author known for the lively style of his popular books on the lives of insects. Biography Fabre was born on 21 December 1823 in Saint-L� ...

, he observed the habits of ants, wasps and bees. He came to America in 1938 to work with B.H. Willier at Rochester, New York. After receiving his doctorate at Columbia University he moved to Johns Hopkins and later to the laboratory of

Alfred Mirsky Alfred Ezra Mirsky (October 17, 1900 – June 19, 1974) was an American pioneer in molecular biology. Mirsky graduated from Harvard College in 1922, after which he studied for two years at the Columbia University College of Physicians and Surgeon ...

Rockefeller University The Rockefeller University is a private biomedical research and graduate-only university in New York City, New York. It focuses primarily on the biological and medical sciences and provides doctoral and postdoctoral education. It is classif ...

, where he studied the structure of chromosomes. He then went to the zoology department of the University of Wisconsin-Madison in 1949, where he started to work with electron microscopes. In 1972 he established the High Voltage Electron Microscopy (HVEM) laboratory within the University of Wisconsin-Madison. He retired at age 75, but remained Emeritus Investigator of the University of Wisconsin’s Integrated Microscopy Resource (IMR) and continued to work on high-resolution images of the nuclear pore complex.

Hans Ris Seminar Series

Th
Laboratory of Optical and Computational InstrumentationLOCI
in collaboration with th
Center for Quantitative Cell Imaging
at th
University of Wisconsin-Madison
hosts an annual seminar series honoring Ris, who oversaw the installation of one of the nation's first high-voltage electron microscopes in the former location o
LOCI
Ris remained Emeritus Investigator of the IMR until his death in 2004. Hans Ris Seminar Series Featured Speakers: 2022
Wolfgang Baumeister
Max Planck Institute of Biochemistry 2019
Davi Bock
University of Vermont and Janelia Farms 2018
Tatyana Svitkina
University of Pennsylvania 2017
Erik M. Jorgensen
University of Utah 2016
David H. Hall
Albert Einstein College 2015
Kent McDonald
UC Berkeley 2014
Wah Chiu
Baylor College of Medicine 2013
Thomas Müller-Reichert
Technische Universität Dresden 2012
Mark E. Ellisman
UC San Diego

Selected works

* Mirsky, A. E., and Hans Ris. "Variable and constant components of chromosomes." ''Nature'' 163.4148 (1949): 666-666. * Mirsky, A. E., and Hans Ris. "The desoxyribonucleic acid content of animal cells and its evolutionary significance." ''The Journal of general physiology'' 34.4 (1951): 451. * Peterson, JOAN B., and Hans Ris. "Electron-microscopic study of the spindle and chromosome movement in the yeast Saccharomyces cerevisiae." ''Journal of cell science'' 22.2 (1976): 219-242.

References

External links

Memorial Resolution of the faculty of the University of Wisconsin-Madison

microscopy.wisc.edu/hansris

Hans Ris – from chromatin fibres, through nuclear tracks, to nuclear pores

Electron Microscopy image of female chromosome by H. Ris
{{DEFAULTSORT:Ris, Hans 1914 births 2004 deaths Scientists from Bern American biologists Members of the United States National Academy of Sciences Cell biologists 20th-century biologists Swiss emigrants to the United States