Britten davidson model. Britten & Davidson Model 2022-12-12
Britten davidson model
The Britten-Davidson model is a mathematical model developed in the late 1960s by two researchers, Neville Britten and David Davidson, to explain the behavior of electrons in molecules. It is based on the principles of quantum mechanics, which describe the behavior of particles at the atomic and subatomic scales.
One of the key features of the Britten-Davidson model is that it takes into account the interaction between electrons, which is known as electron correlation. This interaction is important because it affects the way that electrons move within a molecule and can have a significant impact on the properties of the molecule.
The Britten-Davidson model uses a mathematical technique called perturbation theory to calculate the effect of electron correlation on the behavior of electrons in a molecule. This involves dividing the problem into two parts: the unperturbed problem, which represents the behavior of the electrons without considering electron correlation, and the perturbation, which represents the effect of electron correlation. The two parts are then combined to give a more accurate description of the behavior of the electrons.
One of the major advantages of the Britten-Davidson model is that it allows researchers to make more accurate predictions about the behavior of molecules than other models. This is particularly useful in the field of computational chemistry, where researchers use computers to simulate the behavior of molecules and predict their properties.
In addition to its use in computational chemistry, the Britten-Davidson model has also been applied to a wide range of other areas, including materials science and drug design. Its ability to accurately describe the behavior of electrons in molecules has made it an important tool in many fields of scientific research.
Despite its successes, the Britten-Davidson model has some limitations. It can only be applied to systems with a small number of electrons, and it is not as accurate as more advanced models that take into account a wider range of factors. However, it remains an important and widely used model in the field of chemistry and continues to be an active area of research.
Britten & Davidson Model
. The sensor sites are also regulatory sequences that are recognized by external stimuli, e. At least one integrator gene is present adjacent to each sensor site. The repetition of integrator genes and receptor sites is consistent with the reports that state that sufficient repeated DNA occurs in the eukaryotic cells. If one sensor site is associated with several integrators, it may cause transcription of all integrators simultaneously thus causing transcription of several producer genes through receptor sites.
What is britton
A set of structural genes controlled by one sensor site is termed as a battery. Britten RJ, Davidson EH 1969 Science 165:349; Britten RJ 1998 Proc Natl Acad Sci USA 95:9372. Thus, though a single activator can recognize several genes, different activators may activate the same gene at different times. Its expression is under the control of many receptor sites. The most attractive features of the Britten and Davidson model is that it provides a plausible reason for the observed pattern of interspersion of moderately repetitive DNA sequences and single copy DNA sequences. Cite this entry 2008.
One of the more popular early models known as Britten Davidson model or gene battery model was that given by R. Britten and Davidson proposed that the integrator gene products are activator RNAs that interact directly with the receptor genes to trigger the transcription of the continuous producer genes. A specific receptor site is activated when a specific activator RNA or an activator protein, a product of integrator gene, complexes with it. Sometimes when major changes are needed, it is necessary to activate several sets of genes. The adjacent moderately repetitive DNA sequences would contain the various kinds of regulator genes sensor, integrator and receptor genes.
In: Encyclopedia of Genetics, Genomics, Proteomics and Informatics. At least one such receptor site is assumed to be present adjacent to each producer gene. Repetition of receptor ensures that the same activator recognizes all of them and in this way several enzymes of one metabolic pathway are simultaneously synthesized. This model even though widely accepted, is only a theoretical model and lacks sound practical proof. Sensor site:A sensor site regulates activity of an integrator gene which can be transcribed only when the sensor site is activated.
This is achieved by the multiplicity of receptor sites and integrator genes. Direct evidence indicates that most structural genes are indeed single copy DNA sequences. Transcription of the same gene may be needed in different developmental stages. Each producer gene may have several receptor sites, each responding to one activator. The model predicts the presence of four types of sequences. Producer gen: It is comparable to a structural gene in prokaryotes.
It is also proposed that receptor sites and integrator genes may be repeated a number of times so as to control the activity of a large number of genes in the same cell. The integrator gene products will then interact in a sequence specific manner with receptor genes. Receptor site gene :It is comparable to the operator in bacterial operon. These systems might have operated then in series of interacting batteries. Integrator gene:Integrator gene is comparable to regulator gene and is responsible for the synthesis of an activator RNA molecule that may not give rise to proteins before it activates the receptor site. When sensor genes receive the appropriate signals, they activate the transcription of the adjacent integrator genes.
The external stimuli were supposed to be directed to sensor genes that activated integrator genes that in turn transmitted the signals to receptor genes, which affected than the structural genes, coding for protein. It produces pre mRNA, which after processing becomes mRNA. This model was suggested as a working hypothesis in the 1960s for interpreting the processes involved in the regulation of eukaryotic gene functions. . . .
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