Information, Noise and Communication: Thresholds as Controlling Elements in Development

Abstract

Organisms are dependent on the continual transmission of information both within cells and from outside them. Information is concerned with the conveyance of signals that require both a transmitter and a receiver able to decide what is sent. Accuracy in transmission is degraded by noise, and the evidence that shows noisiness in genetic circuitry is described. Reliable noise coupled with positive feedback constructs probabilistic thresholds amongst a population. In higher plants, stochastic distribution of thresholds enables quantitative variation amongst cells, tissues or plants to variable strengths of signals. It is the function of information to be communicated, but the gel structure of the cytoplasm together with the ordering by structured water might instead increase noise in transmission by interfering with the necessary movement of molecules in signal transduction. To reduce potential noise in signal transmission and transduction, it is suggested that abrupt phase transitions in microdomains of the cytoplasmic gel structure are induced by cytoplasmic calcium, amongst other signals. Plasmodesmata also contain actin gels, and communication between cells may simply be controlled by abrupt gel phase transitions. Two threshold phenomena are thus seen in plant cells important during development. The first involves noise and positive feedback; the second, gel phase transition.

Information Processing and Distributed Computation in Plant Organs

“…Like in the case of flowering, the input of low temperatures lead to an output in the form of the breaking of seed dormancy [48]. The antagonistically acting hormones abscisic acid (ABA) and gibberellic acid (GA) underpin the decision to germinate [49], and is proposed to follow a ratio-based thresholding mechanism [46,50].…”

Single-seed oxygen consumption measurements and population-based threshold models link respiration and germination rates under diverse conditions

“…that individual rates of metabolism and of developmental progress are proportional to the extent by which a given regulatory factor exceeds individual base sensitivity levels, applies to what have previously been thought to be quantitative rather than quantal responses. The combination of this simple threshold response mechanism with its expression cumulatively across populations of individuals that vary in the values of their response thresholds appears to be a fundamental organizing principle of the biology of multicellular organisms, and even of subcellular molecular interactions Population analysis of single-seed oxygen consumption 217 (Bradford and Trewavas, 1994;Trewavas, 2012Trewavas, , 2014Bassel et al, 2014;Angel et al, 2015;Bintu et al, 2016). As technologies for detecting and measuring the metabolic and developmental behaviour of individuals at all levels of biological organization improve, further applications of PBT-based analytical approaches will provide revealing insights.…”

Intelligence, Cognition, and Language of Green Plants

“…Roots do learn about gravity signals and then construct the equipment to more sensitively respond. Other spontaneity is exhibited by situations in which an increasing strength of signal results in more tissues or cells responding and seed germination is a typical example of many others ( Bradford and Trewavas, 1994 ; Trewavas, 2012 ).…”