Joachim Hämmerling
Encyclopedia
Dr. Joachim Hämmerling was a pioneering Danish-German biologist funded by Nazi Germany
who determined the nucleus
of a cell controls the development of organisms by containing the hereditary information, or DNA
. His experimentation with the green alga Acetabularia
provided a model subject for modern cell biological research, and proved the existence of morphogenetic substances, or mRNP
.
. He was educated at the University of Berlin and University of Marburg. He received his doctorate in 1924.
From 1924 to 1931 he was a research assistant at the Kaiser Wilhelm Institute
for Biology, and from 1931 to 1940 a lecturer. In 1940 he became Director of the German-Italian Institute of Marine Biology. In 1942 he became an associate professor of marine biology at the University of Berlin, before becoming the head of the Kaiser Wilhelm Institute for Biology in Langenargen am Bodenseein in 1946. From 1949-1970 he served as the Director of the Max Planck Institute for Marine Biology, ultimately retiring in 1970.
There he discovered that the plant had one cell and the nucleus was always located in the rhizoid
. Then he began studying the roles of the nucleus
and cytoplasm
by experimenting with the Acetabularia
.
In 1938 while working at the Kaiser Wilhelm Institute
for Biology, Hämmerling received a grant through a biology division within the Third Reich headed by Konrad Meyer to study exclusively the effect of the nucleus on development.
Acetabularia species called A. mediterranea, in which Hämmerling had removed specific properties. Shortly thereafter, the mediterranea regenerated the removed properties, but with the characteristics from the crenulata species.
This experiment demonstrated that the nucleus contains the genetic information, DNA, and controls development. The experiment also proved the existence of morphogenetic substances, which would eventually become known as mRNP
.
Nazi Germany
Nazi Germany , also known as the Third Reich , but officially called German Reich from 1933 to 1943 and Greater German Reich from 26 June 1943 onward, is the name commonly used to refer to the state of Germany from 1933 to 1945, when it was a totalitarian dictatorship ruled by...
who determined the nucleus
Cell nucleus
In cell biology, the nucleus is a membrane-enclosed organelle found in eukaryotic cells. It contains most of the cell's genetic material, organized as multiple long linear DNA molecules in complex with a large variety of proteins, such as histones, to form chromosomes. The genes within these...
of a cell controls the development of organisms by containing the hereditary information, or DNA
DNA
Deoxyribonucleic acid is a nucleic acid that contains the genetic instructions used in the development and functioning of all known living organisms . The DNA segments that carry this genetic information are called genes, but other DNA sequences have structural purposes, or are involved in...
. His experimentation with the green alga Acetabularia
Acetabularia
Acetabularia is a genus of green algae, specifically of the Polyphysaceae family, Typically found in subtropical waters, Acetabularia is a single-celled organism, but gigantic in size and complex in form, making it an excellent model organism for studying cell biology...
provided a model subject for modern cell biological research, and proved the existence of morphogenetic substances, or mRNP
Ribonucleoprotein
Ribonucleoprotein is a nucleoprotein that contains RNA, i.e. it is an association that combines ribonucleic acid and protein together. A few known examples include the ribosome, the enzyme telomerase, vault ribonucleoproteins, and small nuclear RNPs , which are implicated in pre-mRNA splicing and...
.
Early life and profession
Joachim August Wilhelm Hämmerling was born March 9, 1901 in BerlinBerlin
Berlin is the capital city of Germany and is one of the 16 states of Germany. With a population of 3.45 million people, Berlin is Germany's largest city. It is the second most populous city proper and the seventh most populous urban area in the European Union...
. He was educated at the University of Berlin and University of Marburg. He received his doctorate in 1924.
From 1924 to 1931 he was a research assistant at the Kaiser Wilhelm Institute
Kaiser Wilhelm Institute
The Kaiser Wilhelm Society for the Advancement of Science was a German scientific institution established in 1911. It was implicated in Nazi science, and after the Second World War was wound up and its functions replaced by the Max Planck Society...
for Biology, and from 1931 to 1940 a lecturer. In 1940 he became Director of the German-Italian Institute of Marine Biology. In 1942 he became an associate professor of marine biology at the University of Berlin, before becoming the head of the Kaiser Wilhelm Institute for Biology in Langenargen am Bodenseein in 1946. From 1949-1970 he served as the Director of the Max Planck Institute for Marine Biology, ultimately retiring in 1970.
Acetabularia experiments
Hämmerling began growing Acetabularia in laboratories in the 1930s.There he discovered that the plant had one cell and the nucleus was always located in the rhizoid
Rhizoid
Rhizoids are thread-like growths from the base or bottom of a plant, found mainly in lower groups such as algae, fungi, bryophytes and pteridophytes, that function like roots of higher plants ....
. Then he began studying the roles of the nucleus
Atomic nucleus
The nucleus is the very dense region consisting of protons and neutrons at the center of an atom. It was discovered in 1911, as a result of Ernest Rutherford's interpretation of the famous 1909 Rutherford experiment performed by Hans Geiger and Ernest Marsden, under the direction of Rutherford. The...
and cytoplasm
Cytoplasm
The cytoplasm is a small gel-like substance residing between the cell membrane holding all the cell's internal sub-structures , except for the nucleus. All the contents of the cells of prokaryote organisms are contained within the cytoplasm...
by experimenting with the Acetabularia
Acetabularia
Acetabularia is a genus of green algae, specifically of the Polyphysaceae family, Typically found in subtropical waters, Acetabularia is a single-celled organism, but gigantic in size and complex in form, making it an excellent model organism for studying cell biology...
.
In 1938 while working at the Kaiser Wilhelm Institute
Kaiser Wilhelm Institute
The Kaiser Wilhelm Society for the Advancement of Science was a German scientific institution established in 1911. It was implicated in Nazi science, and after the Second World War was wound up and its functions replaced by the Max Planck Society...
for Biology, Hämmerling received a grant through a biology division within the Third Reich headed by Konrad Meyer to study exclusively the effect of the nucleus on development.
1943 breakthrough
The groundbreaking experiment came in 1943 when he determined the role of the nucleus. In his experiments, he removed the nucleus from a specific species of Acetabularia called A. crenulata and grafted it onto the cell of another aAcetabularia species called A. mediterranea, in which Hämmerling had removed specific properties. Shortly thereafter, the mediterranea regenerated the removed properties, but with the characteristics from the crenulata species.
This experiment demonstrated that the nucleus contains the genetic information, DNA, and controls development. The experiment also proved the existence of morphogenetic substances, which would eventually become known as mRNP
Ribonucleoprotein
Ribonucleoprotein is a nucleoprotein that contains RNA, i.e. it is an association that combines ribonucleic acid and protein together. A few known examples include the ribosome, the enzyme telomerase, vault ribonucleoproteins, and small nuclear RNPs , which are implicated in pre-mRNA splicing and...
.