What distinguishes the elephant from E. coli. Jacques Monod famously said that ‘What is true for E. coli is true for the elephant.’ While this might be correct in the basic sense that both use nucleic acids and proteins, it is no longer clear that they use them in quite the same way. The many qualitative differences in the biomolecular constitution and mechanisms of protozoans and metazoans, from the proportions of non-coding DNA to those of multidomain and disordered proteins and the mechanisms of gene regulation, seem to reflect different generic principles in how the two types of organism operate at the molecular and cellular levels. Here I suggest that one way to think about those differences is as a shift in the locus of biological causation – a shift that has implications for making biomedical interventions in humans.

Philip Ball
Journal of Biosciences 48, 14 (2023) – Read more