Göran K Hansson,
the secretary general of the Royal Swedish Academy of Sciences said: “This
year’s prize is about the cell’s tool box for repairing DNA.” Together, the
repair mechanisms discovered by Lindahl, Sancar and Modrich fix thousands of
DNA faults caused by UV rays, cigarette smoke, and other toxic substances. They
are constantly at work to repair copying errors as cells divide. Without these
repair mechanisms, the genomes would be riddled with errors, and cancer would
be rife. (A)
PROCESS:
Lindahl,
Modrich, and Sancar were honored for mapping and explaining how cells repair
their DNA and safeguard genetic information. They worked out how cells repair
faults that inevitably occur when DNA is copied several times allowing for
mutations to arise under a wide variety of environmental factors such as UV
rays in sunlight that could inevitably result in skin cancer.
Lindahl searched
for enzymes that would repair faulty genetic material, focusing on the
weaknesses of the DNA letters paired up. Cytosine pairs only with Guanine,
however when Cytosine loses an amino group- it pairs up with Adenine instead.
This error in pairing in the stands cultivates a mutation the next time it is
copied. He realized that cells MUST have a way to protect themselves from this
and in 1974 Lindahl published the details of the enzyme responsible. (A)
Aziz Sancar
Born: 1946, Savur, Turkey
Affiliation at the time of the award: University of
North Carolina, Chapel Hill, NC, USA
Prize motivation: "for mechanistic studies of
DNA repair"
Prize share: 1/3
Paul Modrich
Born: 1946
Affiliation at the time of the award: Howard Hughes
Medical Institute, Durham, NC, USA, Duke University School of Medicine, Durham,
NC, USA
Prize motivation: "for mechanistic studies of
DNA repair"
Prize share: 1/3
Tomas Lindahl
Born: 1938, Stockholm, Sweden
Affiliation at the time of the award: Francis Crick
Institute, Hertfordshire, United Kingdom, Clare Hall Laboratory, Hertfordshire,
United Kingdom
Prize motivation: "for mechanistic studies of
DNA repair"
Prize share: 1/3
CONCLUSION:
The committee
stated that, “Their systematic work has made a decisive contribution to the
understanding of how the living cell functions, as well as providing knowledge
about the molecular causes of several hereditary diseases and about mechanisms
behind both cancer development and ageing,” adding, “All chemical
processes are prone to random errors. Additionally, your DNA is subjected on a
daily basis to damaging radiation and reactive molecules. In fact, you ought to
have been a chemical chaos long before you even developed into a foetus."
(A)
LINKS:
(A)
http://www.theguardian.com/science/2015/oct/07/lindahl-modrich-and-sancar-win-nobel-chemistry-prize-for-dna-research
(B)
nobelprize.org