Central Dogma

The original Central Dogma of molecular biology (left) and its modification in light of the discovery of viruses (right). 

What Crick called the "central dogma of molecular genetics" says that the function of DNA is to store information and pass it on to RNA. The function of... 

The hypothesis that our biological world built on the DNA-RNA-protein central dogma was preceded by an RNA world in which RNA molecules carried both the genetic information and executed the gene functions (through ribozyme activity) is now widely accepted [130]. However, it is also well recognized that RNA due to its vulnerability to hydrolysis - especially as a result of catalysis by divalent metal ions - would not have been able to evolve in a harsh pre-biotic environment Also the formation of RNA under presumed pre-biotic conditions is extremely inefficient It is not so far-fetched to propose that a peptide nucleic acid-like molecule may have been able to function as a form of pre-biotic genetic material since it... 

DNA has two broad functions replication and expression. First, DNA must be able to replicate itself so that the information coded into its primary structure is transmitted faithfully to progeny cells. Second, this information must be expressed in some useful way. The method for this expression is through RNA intermediaries, which in turn act as templates for the synthesis of every protein in the body. The relationships of DNA to RNA and to protein are often expressed in a graphic syllogism called the central dogma. The concept was proposed by Crick in 1958 and was revised in 1970 to accommodate the discovery of the RNA-dependent DNA polymerase. Crick s original theory suggested that the flow of information was always from RNA to protein and could not be reversed, yet it allowed for the possibility of DNA synthesis from RNA. 

The total human complement of neurons is laid down around birth, and if they die they cannot be replaced - unlike most cells in our body. However, this central dogma of neuroscience has been challenged by the recent finding that neurogenesis can occur in the adult rat hippocampus, and these new cells seem to be required for at least one type of memory (Shors et al., 2001). Whether this will also be the case in... 

Sarkar, S. (1996a), Biological information a skeptical look at some central dogmas of molecular biology , in S. Sarkar (Ed.), The Philosophy and History of Molecular Biology New Perspectives, Kluwer, Dordrecht, The Netherlands, pp. 187-231... 

Fig, 2. Representation ofthe central dogma ofmolecular biology. Immunoelectron microscopy accompanies many other techniques used to study gene expression including in situ hybridization. 

Molecular biology involves the study of the major macromolecules, DNA, RNA, and protein. The central dogma ofmolecular biology is illustrated in Fig. 2. The central dogma shows the relationship among the macromolecules in the processes of transcription and translation. Figure 2 also gives the relationship between immunoelectron microscopy and in situ hybridization. In situ hybridization allows one to localize a specific nucleic acid sequence. Immunoelectron microscopy is an essential component to the technique of in situ hybridization when applied at the EM level. 

The flow of information from DNA to RNA to proteins is one of the fundamental prindples of molecular biology. It is so important that it is sometimes called the "central dogma."... 

The central dogma of apoptosis is that all the initiating pro-apoptotic stimuli converge on the mitochondrial compartment. Thus, although apoptosis can be initiated elsewhere, the execution phase of apoptosis induced by ionizing radiation needs mitochondria. How do DNA lesions trigger mitochondria Several metabolic pathways coimect mitochondria to the nucleus. 

The central dogma of molecular biology and protein synthesis... 

Francis Crick enunciated the central dogma of molecular biology in 1958 DNA directs its own replication and its transcription to RNA that, in turn, directs its translation to protein. This statement is frequently oversimplified to DNA makes RNA makes protein. ... 

The central dogma of molecular biology was first defined by Francis Crick. See R. Olby, Francis Crick, DNA, and the Central Dogma . Daedalus Fall 1970, pp 970-986. 

Figure 20.18 The central dogma of molecular biology a summary of processes involved inflow of genetic information from DNA to protein. The diagram is a summary of the biochemical processes involved in the flow of genetic information from DNA to protein via RNA intermediates. This concept had to be revised following the discovery of the enzyme, reverse transcriptase, which catalyses information transfer from RNA to DNA (see Chapter 18). It may have to be modified in the future since changes in the fatty acid composition of phospholipids in membranes can modily the properties of proteins, and possibly their functions, independent of the genetic information within the amino acid sequence of the protein (See Chapters 7, 11 and 14).

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