Has any one of you thought of chaos to be good? Generally, in our day-to-day life, chaos means doom. But what if this exact chaos was helpful in letting life thrive at a microscopic level? Biologists have taken that as the general rule, but now what if this were discovered to be helpful in letting life thrive at a microscopic level? That is exactly what a team of scientists from the University of Southern California has found out, and they could feel it’s going to turn out to be a new bedrock principle of biology.
Traditionally used rules by biology in its pursuit to understand the natural world are generally broad generalizations for which the patterns vary between living organisms. Examples are Allen’s rule, which says that limb lengths and thicknesses of warm-blooded animals in colder climates are shorter and thicker to help the system retain body heat, whereas similarly sized animals in hot climes have longer and thin limbs to dissipate heat. Another rule is Bergmann’s rule, that species are larger in colder climates but smaller in warmer ones.
Now USC molecular biologist John Tower would like to add a new one that he has christened “selectively advantageous instability,” or SAI. The name is a mouthful, but the underlying concept is both interesting and fairly revolutionary. Tower says a little instability at the cellular level, either in proteins or the genetic material itself, sometimes turns out to be useful for organisms. The finding pushes against the general belief that stability is invariably best for biological processes.
It sounds strange, but cells appear to have a sweet tooth for controlled chaos. “Even the simplest cells contain proteases and nucleases and regularly degrade and replace their proteins and RNAs, showing that SAI is required for life,” Tower says. Think of it as a kind of cellular housekeeping. Cells are constantly building. What they do is, they toggle between two states—one in which the unstable component is ‘on’ and one in which it is ‘off’. Curiously, however, it could be this toggling that allows cells to gain an edge.
How does this work? The coexistence of the usual gene and its mutated version in the same population of cells actually can be quite beneficial for an organism. For example, both variants of genes may benefit under different conditions. One would help a cell to survive when there is significant stress; under normal conditions, another version works best. Genetic diversity may make an organism as a whole more resistant.
It’s not all milk and honey, however. Instability at this level comes energy and resource-expensively and has its downsides, especially in regard to aging. In maintaining this precarious balance is a cell that makes a lot of investments in energy, which can end up being part of the wear and tear we associate with aging. “Again, there is evidence that aging is hard to define,” the researchers argue. “Most definitions, however, include that there is an increased liability of death with age and a decreased reproductive fitness with age.” That, in essence, is what is taking place: very processes that assist in maintaining the health of cells within the short term might actually add to the aging procedure in the long term.
It turns out that selectively advantageous instability doesn’t have implications only for cellular health and aging but probably for a few of the most fascinating areas of science today: chaos theory, criticality, even cellular consciousness. Tower is sanguine about the broad implications: “Depending upon the research question being addressed, SAI has been shown to be important for production of each of these phenomena.”.
A discovery of this nature would not only fundamentally be new in itself but also explain several long-established biological phenomena. It goes consistent with chaos theory, The work on the systems apparently disordered yet being controlled by deterministic laws. The notion of cellular consciousness itself—something like cells making decisions in some manner likewise starts fitting more into order under SAI.
What all this really means for the future of biology is, if SAI enriches into conventional wisdom, it is expected to help scientists join the other “rules” in shedding some light on mechanisms of disease and processes of aging. Who knows? Probably one fine day, it will translate into breakthrough treatments against age-related diseases or new strategies aimed at raising healthy human life spans.
This new appreciation of cellular chaos thus brings with it even more exciting avenues of research, putting a newer light on the complexity and adaptability of life. In the future, by plumbing deeper into the intricate details lying within selectively advantageous instability, we literally shall stand at the threshold of a totally new epoch in the biological sciences: one in which chaos is not an evil to be surmounted but actually part of the equation.
