Cells contain several kinds of organelles. An organelle (ôrɡəˈnel) is any of a number of organized or specialized structures inside a living cell. Ribosomes are among the most crucial organelles in cells. Here, we tell the story of how ribosomes were discovered.

Organelles are important to you. For instance, from time to time, you will get sick. We usually blame sickness on some problem with our organs. Examples include lungs when we get the flu; or muscle when we have a bruise; or skin when we get sunburned. All disease begins with damage to one or more organelles within cells. The organelles allow cells to run smoothly when we are well.

Well now, you might ask, “Why should I care about how an organelle was discovered?” First, the discoveries of the various organelles tell a story about how scientists make discoveries. The story typically tells about how gaps in existing knowledge lead to new questions that motivate the scientist to develop a plan for testing.

Before we begin Dr. Palade’s story, it helps to see how centuries of work on other organelles came before Palade. It all began with Robert Hooke, who invented a microscope that he used to magnify objects enough so that cells became visible. He worked with cork, which is actually dead tissue from the cork tree. What he saw were empty circles that he named “cells” because they reminded him of a prison cell that holds prisoners. But that raised a question that Hooke could not answer: “What did these cells contain when the plant was alive?”

Over the years, many other people with better equipment and ideas found the answers. To provide a little historical perspective, here is a list of major organelles and when they were discovered.

Meet the Scientist,

George Palade

1912-2008

Dr. George Palade is considered by many to be the father of modern cell biology. He developed a unique way to separate the various organelles in cells. His method was valuable because it allowed organelles of a cell to be separated from each other with little damage. As a result, it was possible to learn the normal function of organelles. Dr. Palade also discovered ribosomes and their function and provided us with new information about other cell organelles. Because he could purify ribosomes without damage, he was able to discover their function in protein synthesis. This is turn helped other researchers find treatments for such diseases as cancer, anemia, bone marrow failure, and various genetic diseases.

George Palade was born in 1912 in Jassy (Iasi), the old capital of Moldavia, Romania. His father was a philosophy professor, and his mother was a teacher. In 1930, he started medical school in Romania at the University of Bucharest. During medical school he discovered that he was more interested in basic science than in medicine. After medical school, he started work on a PhD degree studying dolphin kidneys. He was trying to understand how the kidneys of marine mammals, such as dolphins, are able to get rid of all of the salt that is found in sea water. Little did he know that he was about to become a pioneer in cell biology.

During World War II, he served in the medical corps of the Romanian army. After the war, he came to the United States to continue his studies. In 1952, he became a citizen of the United States. While working for a few months in the biology laboratory of Robert Chambers at New York University, Palade met Dr. Albert Claude who was giving a seminar on his work with electron microscopy (EM). This technology magnified organelles enough to be seen. That stimulated Dr. Palade’s interest in organelles. After the seminar, he chatted with Claude and somehow managed on the spot to get invited to work in Claude’s lab at The Rockefeller Institute for Medical Research.

During the 1950s, Dr. Palade discovered ribosomes and their function. He also defined the fine structure of mitochondria (Figure 1).