Antibody Diversity Mechanism

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A transposition- like mechanism can be used for other types of DNA rearrangement reactions. Such mechanism is responsible for assembly of gene fragments during development of the vertebrate immune system. Vertebrates have two specialized cells namely T- cells and B-cells that dedicated to recognize the invading organism. B cells produce antibodies that circulate in the bloodstream. T-cell produce cell surface- bound receptor protein called T-cell receptor. These classes of protein able to recognized great diverse invader molecule then starts a cascade event to destruct the invader.
Antibody diversity is generated by the rearrangement of variable region gene segments during the differentiation of the antibody- producing cells by a series of sequence-specific DNA rearrangement (Watson, Baker, Bell, Gann, Levine, & Losick, 2008). Antibodies are constructed of two copies each of a light chain and a heavy chain. The antigen binding site is constructed from VL and VH domains of the antibody molecule whereby sequence in this region is highly variable (Watson et al., 2008)). There is also domain of the antibody where the regions do not differ among different antibody molecules and is called “C” or constant. In developing B cells, DNA sequences of immunoglobulin unable to express directly from germ line so the individual gene segments must be rearrange to assemble a functional gene. During the development of B cells the V and J light-chain segments are spliced and join random by somatic recombination process. These segments are then brought together with CL-coding region by RNA splicing. Recombination produces variants of antibody chain.
There are several mechanisms of generation of antibody diversity in human. Figure 1 below shows the f...

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...r discarded (Watson et al., 2008).

Works Cited

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Watson, J. D., Baker, T. A., Bell, S. P., Gann, A., Levine, M., & Losick, R. (2008). New York: Cold Spring Harbor. .
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