Friday, December 14, 2012

The Algorithmic Origins of Life

Revolutionary Paper Tackles Definition of Life. 
In the newly published paper “The Algorithmic Origins of Life,” (1) Paul Davies and Sara Walker try to tackle the definition of life, and its evolution, from an informational system perspective rather than from the chemistry and the physical properties of the molecules that might have existed at the time on the planet. This is a unique and quite revolutionary way of re-conceptualizing what defines life and what would be needed to sustain, reproduce and evolve it.

Logical First Steps?
They begin by reviewing the analog versus the digital systems of information. The cell contains both an analog system (the continuous biochemical interactions between molecules in the cytoplasm) and a digital system (DNA) which is separate. Presently the favored idea of the original molecule of life is RNA. But as the paper argues, RNA is an extremely unstable molecule, susceptible to degradation by hydrolysis and difficult to synthesize in the first place under the conditions originally present on earth.

Sunday, December 2, 2012

The Human Genome is Chaotic

Premature Predictions proven incorrect. 
The story of the human genome is no longer about gene structure. To say that our enthusiasm was premature and our predictions bombastic after the human genome was mapped is an understatement. The evolutionary unit is not the gene—though genes do compete—but the complete cell or organism. Cell functions depend on the millions of regulatory interactions between the protein-coding genes, which comprise less than 2% of the genome, and the non-protein-coding genes which form the regulatory mechanism of gene expression. The recent ENCODE studies have given a glimpse of the immense complexity of the network of interrelated biofeedback loops of gene repressors and de-repressors which comprise an active, non-linear system. It is clear that we have only scratched the surface and that the genome will be shown to be even more complex.

Fractal Geometric Properties. 
One of the most significant discoveries in genomics is that the genome (1,2) as well as the cytoplasm (3) have chaotic fractal properties.