Jeffrey C. Hall facts for kids

Quick facts for kids Jeffrey C. Hall
Jeffrey C. Hall at Nobel Prize press conference in Stockholm, December 2017
Born	Jeffrey Connor Hall (1945-05-03) May 3, 1945 (age 80) New York City, U.S.
Education	Amherst College (BA) University of Washington, Seattle (MS, PhD)
Known for	Cloning the period gene
Awards	Genetics Society of America Medal (2003) Gruber Prize in Neuroscience (2009) Louisa Gross Horwitz Prize (2011) Gairdner Foundation International Award (2012) Shaw Prize (2013) Wiley Prize (2013) Nobel Prize in Physiology or Medicine (2017)
Scientific career
Fields	Genetics
Institutions	Brandeis University University of Maine
Thesis	Genetic analysis of two alleles of a recombination-deficient mutant in drosophila melanogaster (1971)
Doctoral advisor	Lawrence Sandler
Other academic advisors	Seymour Benzer, Herschel L. Roman

Jeffrey Connor Hall (born May 3, 1945) is an American geneticist and chronobiologist. He is a retired professor of biology at Brandeis University.

Hall spent his career studying the brains and behaviors of fruit flies. His research on Drosophila melanogaster helped us understand how circadian clocks work. These are like our body's internal clocks. He also learned about how male and female traits develop in the nervous system.

In 2017, Jeffrey Hall, along with Michael W. Young and Michael Rosbash, won the Nobel Prize in Physiology or Medicine. They received the award for discovering how our bodies keep track of time, like why we feel sleepy at night.

Life and Discoveries

Early Life and Education

Jeffrey Hall was born in Brooklyn, New York. He grew up near Washington D.C., where his father worked as a reporter. His father encouraged him to read the daily newspaper and stay updated.

Hall went to Walter Johnson High School and graduated in 1963. He first planned to study medicine. But at Amherst College, he found a passion for biology. For a school project, he worked with Philip Ives, who became a big influence.

In Ives' lab, Hall became fascinated with studying Drosophila (fruit flies). He studied how their genes change and move around. His success led him to graduate school at the University of Washington in Seattle.

Starting His Science Career

In 1967, Hall began working in Lawrence Sandler's lab. He studied how enzymes in fruit flies changed with age. He also looked at how chromosomes behave during cell division.

After getting his PhD, Hall joined Seymour Benzer's lab in 1971. Benzer was a pioneer in genetics. There, Hall learned about the brain structure and chemistry of fruit flies. In 1974, Hall became a professor at Brandeis University.

Challenges in Science

Working on biological clocks was not always easy for Hall. Many traditional scientists were unsure about his new ideas. He faced doubts when trying to prove the importance of certain proteins he found.

Hall also found the process of getting research funding difficult. He felt that strict rules sometimes stopped scientists from exploring new ideas. He believed that funding should give scientists freedom to follow their curiosity. Even though he loved his research, these challenges made him step away from the field later on.

Discovering the period Gene

In the late 1970s, Hall worked with Florian von Schilcher. They found parts of the fruit fly brain that control male courtship songs. Hall realized that these songs were a great way to study behavior.

With Bambos Kyriacou, Hall discovered that fruit flies sing rhythmically, about once every minute. They wondered if the period gene, known for affecting sleep cycles, also affected these songs.

They tested fruit flies with different period gene changes. They found that these changes affected the courtship songs in the same way they affected daily rhythms. For example, one change made the song cycle shorter, another made it longer, and one made it have no regular rhythm at all.

Understanding Fruit Fly Behavior

Hall also studied fruit flies with a gene called fruitless gene. Flies with this gene were sterile and would try to court both males and females, but couldn't mate. This behavior was known since the 1960s, but Hall's group studied it more closely.

In the mid-1990s, Hall worked with Bruce Baker and Barbara Taylor. They successfully copied the fruitless gene. Their research showed that fruitless is a master control gene for courtship behavior. When certain proteins from this gene were missing, male flies hardly courted females. They also failed to produce the pulse song and showed more courtship towards other males.

The Body's Internal Clock

How PER Protein Regulates Itself

In 1990, Hall worked with Michael Rosbash and Paul Hardin. They found that a protein called Period (PER) helps control its own creation. They developed a model that explained how this works.

In this model, the period gene makes PER protein. When there's enough PER, it tells the gene to slow down. This causes PER levels to drop, which then allows the gene to start making more PER again. This cycle is a key part of the body's internal clock.

How Cells Synchronize

In 1997, Hall and his team found that genes for the internal clock are active in cells all over the body. Even though these genes were important, their activity levels varied in different body parts.

Hall later discovered in 2003 how these cells stay in sync. He found that a protein called pigment dispersing factor (PDF) helps control the daily rhythms. This protein is found in specific brain cells of the fruit fly. Hall concluded that these brain cells act as the main timekeeper, and PDF helps all the other cells keep time together.

Improving the Clock Model

In 1998, Hall made two more important discoveries about the fruit fly's internal clock. He found that a protein called Cryptochrome (CRY) is important for setting the clock using light. He thought CRY might not just be an input, but also part of the clock itself.

In the same year, Hall discovered how the period and timeless genes are controlled. He found that two proteins, CLOCK and Cycle (CYC), join together. They then attach to a specific part of the genes, which turns on the production of period and timeless messages. This helps control the timing of the internal clock.

See also

In Spanish: Jeffrey C. Hall para niños