review articles
Doi: 10.1145/1506409.1506427
The convergence of CS and biology will serve
both disciplines, providing each with greater
power and relevance.
BY coRRaDo PRiami
algorithmic
systems
Biology
throughout the hiStory
of computer science, leading
researchers—including Turing, von Neumann, and
Minsky—have looked to nature. This inspiration
has often led to extraordinary results, some of which
acknowledged biology even in their names: cellular
automata, neural networks, and genetic algorithms, for
example.
Computing and biology have been converging ever
more closely for the past two decades, but with a vision
of computing as a resource for biology. The resulting
field of bioinformatics addresses structural aspects
of biology, and it has produced databases, pattern
manipulation and comparison methods, search tools,
and data-mining techniques. 47, 48 Bioinformatics’ most
notable and successful application so far has been the
Human Genome Project, which was made possible by
the selection of the correct abstraction for representing
DNA (a language with a four-character alphabet). 48 But
things are now proceeding in the reverse direction as
well. Biology is experiencing a heightening of
interest in system dynamics by interpreting living organisms as information manipulators. 30 It is thus moving toward “systems biology.” 31 There
is no general agreement on systems
biology’s definition, but whatever we
select must embrace at least four characterizing concepts. Systems biology is
a transition:
˲ From qualitative biology toward a
quantitative science;
˲ From reductionism to system-level
understanding of biological phenomena;
˲From structural and static descriptions to functional and dynamic
properties; and
˲ From descriptive biology to mecha-nistic/causal biology.
These features highlight the fact that
causality between events, the temporal
ordering of interactions and the spatial
distribution of components are becoming essential to addressing biological
questions at the system level. This development poses new challenges to describing the step-by-step mechanistic
components of phenotypical phenomena, which bioinformatics does not address. 9
One of the philosophical foundations of systems biology is mathematical modeling, which specifies and tests
hypotheses about systems; 7 it is also
a key aspect of computational biology
because it deals with the solution of
systems of equations (models) through
computer programs. 37 Solution of systems of equations is sometimes termed
“simulation.” By whatever name, the
main concept to be exploited involves
instead algorithms and the (
programming) languages used to specify them.
We can then recover temporal, spatial,
and causal information on the modeled systems by using well-established
computing techniques that deal with
program analysis, composition, and
verification; integrated software-development environments; and debugging
tools as well as computational complexity and algorithm animation. The
convergence between computing and
systems biology on a peer-to-peer basis
is then a valuable opportunity that can