Information pathway

Figure 43-3. The "information pathway." Information flows from the gene to the primary transcript to mRNA to protein. Hormones can affect any of the steps involved and can affect the rates of processing, degradation, or modification of the various products.

One suggestive piece of support that leads to the idea that certain different RNA informed pathways of protein synthesis from amino acids arose in different vesicles is the correlation between the different first and, to some degree, the second... 

Today s understanding of information pathways has arisen from the convergence of genetics, physics, and chemistry in modern biochemistry. This was epitomized by the discovery of the double-helical structure of DNA, postulated by James Watson and Francis Crick in 1953 (see Fig. 8-15). Genetic theory contributed the concept of coding by genes. Physics permitted the determination of molecular structure by x-ray diffraction analysis. Chemistry revealed the composition of DNA. The profound impact of the Watson-Crick hypothesis arose from its ability to account for a wide range of observations derived from studies in these diverse disciplines. 

In this chapter we examine the synthesis of RNA on a DNA template and the postsynthetic processing and turnover of RNA molecules. In doing so we encounter many of the specialized functions of RNA, including catalytic functions. Interestingly, the substrates for RNA enzymes are often other RNA molecules. We also describe systems in which RNA is the template and DNA the product, rather than vice versa. The information pathways thus come full circle, revealing that template-dependent nucleic acid synthesis has standard rules... 

In our discussion of DNA and RNA synthesis up to this point, the role of the template strand has been reserved for DNA. However, some enzymes use an RNA template for nucleic acid synthesis. With the very important exception of viruses with an RNA genome, these enzymes play only a modest role in information pathways. RNA viruses are the source of most RNA-dependent polymerases characterized so far. 

Proteins are the end products of most information pathways. A typical cell requires thousands of different proteins at any given moment. These must be synthesized in response to the cell s current needs, transported (targeted) to their appropriate cellular locations, and degraded when no longer needed. 

Garshnek, V., Burkle, F. M. (1999). Telecommunication systems in support of disaster medicine Applications of basic information pathways. Annals of Emergency Medicine, 34, 213. 

One of many quasiequivalent states metastability recording arbitrary information (pathway) progressive segregation and specialization of information structure... 

Appropriate responses require control systems, and each of these needs sensors, actuators, processing, and information pathways. Survival requires that adequate responses are made to environmental stimuli. Information important to the biological unit must be sensed, sent on to some structure that determines the appropriate response, and then action taken. These controls may be simple or elaborate, but the fact that they occur at all in biology is a sign of life. See Sections 4.3 through 4.5. 

Appropriate responses require control systems, and each of these needs sensors, actuators, processing, and information pathways. 

Partial directed coherence method was used for the analysis of EEG-EEG coherence because it facilitates the information pathways or direction of human brain activities during the two tasks as explained in the previous section. 

Next, the averaged EEG signals passed through partial directed coherence function that calculated the value of PDC to model the information pathways between EEG signals using the equation in (2). Meanwhile, the last step was... 

Fig. 3 The information pathways amongst 19 channels during control task for 4 subjects (S1-S4)...

In control task, the patterns of the information pathways amongst 19 channels were almost identical (Fig. 3). The sources were coming from the anterior and posterior of the frontal lobe. These are because of the muscle contraction and motor control by the subjects. Moreover, the subjects need to plan and organize the contraction within the duration given and concentrate on the motor action. However, there were also some sources that are coming from the occipital lobe for some subjects although the task was without visual stimulation. 

---