How Does Life Begin and Develop?
Objective
1
Sources of 0rganics on Earth
Objective
2
Origin of Life's Cellular Components
Objective
4
Genomic Clues to Evolution
Objective
5
Linking Planetary and Biological Evolution
Does Life Exist Elsewhere in the Universe?
Objective
7
The Extremes of Life
Objective
8
Past and Present Life on Mars
Objective
9
Life's Precursors and Habitats in the Outer Solar System
Objective
10
Natural Migration of Life
Objective
11
Origin of Habitable Planets
Objective
12
Effects of Climate and Geology on Habitability
Objective
13
Extrasolar Biomarkers
What is Life's Future on Earth
and Beyond?
Objective
14
Ecosystem Response to Rapid Environmental Change
Objective
15
Earth's Future Habitability
Objective
16
Bringing Life with Us beyond Earth
Objective
17
Planetary Protection
Question: How Does Life Begin and Develop?
Models for Life
Objective 3: Establish replicating, catalytic systems capable of evolution and construct laboratory models of metabolism in primitive living systems.
To the best of our knowledge, the principal attributes of living systems anywhere in the Universe are their capabilities to replicate, to catalyze the chemical reactions of life, to integrate their diverse components to act in concert to support these activities, and to evolve. Building models that exhibit these properties from nucleic acids, proteins, membrane-forming molecules, other organic molecules and possibly minerals, and establishing the range of conditions under which these systems can operate, will provide essential clues about hypothetical, different life forms that may have arisen beyond the Earth. Such new models for the formation of chemical systems with the attributes of life can be predicted by computer simulations and constructed in laboratory experiments.
Implementation
Near to mid-term:
- Through laboratory experiments,
develop and characterize self-replicating systems based on diverse molecules
and recognition mechanisms.
- Based on in vitro evolution
and rational design, construct simple structures capable of catalyzing
biochemical reactions, driving bioenergetics and performing other functions
of a living system. Demonstrate coupling between these functions.
- Develop a computational research program to describe and understand auto-catalytic reaction networks, self-organization and self-reproduction phenomena, and collective behavior of simple biological systems with and without central (genomic) control.
Future extensions:
- Construct models of self-replicating,
evolving systems, capable of performing the basic functions of a living
system. Relate these models to the environmental conditions in habitable
zones in which they may arise. Of special interest are conditions that
may have existed on Mars and Europa. This could provide clues about
extinct or extant life forms, and generic recognizable features, that
may be found in missions to these bodies.
- Establish the general, physical and chemical principles that drive the emergence of catalytic networks of chemical reactions, self-replication and the formation of cell-like compartments. General models of living systems offer considerable promise for biotechnology.