A close look at Günter Blobel's transformative contributions to
molecular cell biology.
The difficulty of reconciling chemical mechanisms with the functions of
whole living systems has plagued biologists since the development of
cell theory in the nineteenth century. As Karl S. Matlin argues in
Crossing the Boundaries of Life, it is no coincidence that this
longstanding knot of scientific inquiry was loosened most meaningfully
by the work of a cell biologist, the Nobel laureate Günter Blobel. In
1975, using an experimental setup that did not contain any cells at all,
Blobel was able to target newly made proteins to cell membrane vesicles,
enabling him to theorize how proteins in the cell distribute spatially,
an idea he called the signal hypothesis. Over the next twenty years,
Blobel and other scientists were able to dissect this mechanism into its
precise molecular details. For elaborating his signal concept into a
process he termed membrane topogenesis--the idea that each protein in
the cell is synthesized with an "address" that directs the protein to
its correct destination within the cell--Blobel was awarded the Nobel
Prize in Physiology or Medicine in 1999.
Matlin argues that Blobel's investigative strategy and its subsequent
application addressed a fundamental unresolved dilemma that had
bedeviled biology from its very beginning--the relationship between
structure and function--allowing biology to achieve mechanistic
molecular explanations of biological phenomena. Crossing the Boundaries
of Life thus uses Blobel's research and life story to shed light on the
importance of cell biology for twentieth-century science, illustrating
how it propelled the development of adjacent disciplines like
biochemistry and molecular biology.
