Month: September 2022

HARD DRIVE. “Rather, DNA is a (mostly) passive repository for transcription of stored data into RNA, some (but by no means all) of which goes on to be translated into proteins. The biologically relevant information stored in DNA therefore has very little to do with its specific chemical nature (beyond the fact that it is a digital linear polymer).” https://lnkd.in/ewsT9EQ View in LinkedIn

FUNCTIONALITY REVEALS DATA. “The genetic material could just as easily be a different variety of nucleic acid (or a different molecule altogether), as recently experimentally confirmed. It is the functionality of the expressed RNAs and proteins—not the bits—that is biologically important.” https://lnkd.in/ewsT9EQ View in LinkedIn

EMBEDDED. “Functionality, however, is not a local property of a molecule.” https://lnkd.in/ewsT9EQ View in LinkedIn

INTERNAL MILIEU. “The functionality of expressed RNA and protein sequences is clearly context-dependent—only an exceedingly small subset of these molecules is causally efficacious (i.e. meaningful) in the larger biochemical network of a cell whose functioning is dependent on conditions such as salinity of the cytoplasm, pH, etc. That milieu includes other expressed proteins, RNAs, metabolites and a host of other molecules, the spatial distribution of which is crucial to their individual causal roles.” https://lnkd.in/ewsT9EQ View in LinkedIn

DATA NOT ENOUGH. “A priori, it is not possible to determine which will be functional in a cell based on local structure and sequence information alone.” https://lnkd.in/ewsT9EQ View in LinkedIn

SHIFTING MIRAGE. “One is therefore left to conclude that the most important features of biological information (i.e. functionality) are decisively non-local, subject to informational control and feedback, so that the dynamical rules will generally change with time in a manner that is both a function of the current state and the history of the organism (suggesting perhaps that even the concept of evolution itself may be in need of revision.” https://lnkd.in/ewsT9EQ View in LinkedIn

INTRINSIC INFORMATION. “The central position of information in biology is not itself especially new or radical. What is often sidestepped, however, is the fact that in biological systems information is not merely a way to label states, but a property of the system.” https://lnkd.in/ewsT9EQ View in LinkedIn

INFORMATION AS PHENOTYPE. “To be explicit, biological information is distinctive because it possesses a type of causal efficacy —it is the information that determines the current state and hence the dynamics (and therefore also the future state(s)).” https://lnkd.in/ewsT9EQ View in LinkedIn

KEY FEATURE. “We postulate that it is the transition to context-dependent causation—mediated by the onset of information control—that is the key defining characteristic of life.” https://lnkd.in/ewsT9EQ View in LinkedIn

SO ENDS this first of two weekends on the topic of biological information, which many believe is a defining part of what differentiates life from non-life. Prions are at least one exception, being relatively simple molecules that can evolve and reproduce. My favorite take-away from this section is that life is information that can replicate. This completely reframes the question and perspective, and does broadly include quirks like prions. View in LinkedIn