The Discovery Telomerase Essay

The additive chromosomes of eucaryotes are more complex than the round chromosomes of the bacterium. Due to the biochemical belongingss of Deoxyribonucleic acid polymerases. the reproduction of the eucaryotic chromosomes poses a particular job: the care of the length of the additive chromosomes. However. it was discovered that a alone enzyme complex appears to play a important in keeping the length of eucaryotic chromosomes. This enzyme is known as the telomerase. Its regulatory action on the eucaryotic cell implies that it may besides be involved in the procedure of aging and in the development of malignant neoplastic disease cells.

In this paper. the telomerase becomes the focal point of survey. The find. belongingss. and maps of the telomerase inside the eucaryotic cells will be described. based on the recent scientific surveies that have been conducted about them. And eventually. current and possible applications that involve this enzyme. in the field of biotechnology. will be presented. The Discovery of Telomerase When the telomerase was foremost discovered by Carol Greider in 1984. many geneticists and molecular life scientists like her have already been perplexing over the observation that the tips of chromosomes are stabilised by telomeres.

Telomeres are mere parts in the Deoxyribonucleic acid in which subdivisions of them are no longer copied during the procedure of cell division and chromosome reproduction ( Vermolen 2005 ) . But the fact that a little subdivision of a telomere is non copied should ensue in shorter telomeres in the girl cells. Queerly. this does non happen and scientists can merely surmise that something maintains the length of the telomere and it could be an enzyme that is yet unknown. Then. on that fatal Christmas Day in 1984. Greider found the elusive enzyme through the usage of autoradiography ( Skloot 2001 ) .

The telomerase is the enzyme that is responsible for keeping the familial stuff found at the tips of the chromosomes. The Properties of Telomerase The telomerase is an enzyme and this brings to mind two basic features. First. any enzyme is composed of a protein. In the instance of telomerase. the protein is the RNA and it can be considered as a ribozyme ( Brown 2005 ) . And 2nd. any enzyme is a natural accelerator of all chemical reactions within the organic structure of an being. This means that the telomerase facilitates a critical biochemical reaction.

But the exact mechanism that the telomerase executes to keep the length of the telomere during chromosomal reproduction can merely be determined if the belongingss of it are known. And the belongingss can be known if the specific nature of the construction of the RNA is established. The telomerase is composed of two constituents. the indispensable RNA and the TERT. The latter. which stands for telomerase contrary RNA polymerase. is the catalytic protein. It “contains sequence motives homologous to those in the catalytic sphere of rearward RNA polymerase enzymes” ( Chen & A ; Greider 2004. P.

14683 ) . This is concluded because the TERT is remains the same in all eucaryotes. The construction of the RNA constituent. nevertheless. is more ambitious to characterize. This is because the telomerase RNA varies in footings of size and sequence. Fortunately. the overall construction of the telomerase RNA in many ciliophorans and craniates was finally established ( Chen. Blasco & A ; Greider 2000 ) . The common procedure utilized was the phyletic analysis ( Tzfati 2003 ) . However. the word picture of telomerase RNA did non uncover similarities.

There are big differences among the telomerase RNA constructions of different beings. For illustration. the RNA of ciliophorans has a conserved sequence motive found in spiral I ( Lai 2002 ) . where as the RNA of barms seeks several coiling parts as the binding sites for the telomerase’s Est1 protein ( Peterson et al 2001 ) . Therefore. there was a demand to determine a nucleus construction. This nucleus construction is besides referred to as the secondary Blackburn ( 2004 ) and her co-workers. by utilizing telomerase RNAs of barms. proposed a nucleus construction out of the procedure of defining bases and base couplings.

They showed that a pseudoknot construction is an indispensable constituent of the telomerase RNA because it plays an of import function during the binding procedure. Figure 1: The TERT binding and the pseudoknot The Functions of Telomerase The most obvious map of the telomerase. as stated before. is the care of the length of the additive chromosomes of eucaryotes. This is carried out through a procedure known as contrary written text. But. among scientists. this general statement is deficient. particularly before the progressing cognition in biochemistry.

And now that the construction of the telomerase is established. the following inquiry to be answered is how the telomerase really and specifically works. There is no consensus so far. but the consequences of assorted surveies can be combined to organize a better image of the map of telomerase. Here are three of the most important 1s. First. it was steadfastly established by several surveies that there is a long-range base-pairing that occurs at the Est2 binding site ( Chappell & A ; Lundblad 2004 ; Dandjinou et Al 2004 ; Lin et Al 2004 ; Zapulla & A ; Cech 2004 ) .

Second. the pseudoknot performs assorted maps: binding at Est2 among barms and other replication-related activities among craniates ( Livengood et al 2002 ) . And 3rd. the TERT proteins of the telomerase locate specific spheres and these spheres are referred to as motif T. This motive T is critical for RNA binding ( Friedman & A ; Cech 1999 ; Kelleher et Al 2002 ) . The specific actions of the two constituents of the telomerase are critical towards the finding its applications. Current and Potential Applications of Telomerase

There have been several misinterpretations about the application of telomerase in the field of biotechnology. The most popular false impression about telomerase is that it is the fountain of young person. Telomerase does non do a individual stay immature everlastingly. What the telomerase can make is to back up the reproduction of the chromosome and so. after many old ages. let the province of aging. It must be remembered that the telomerase merely act upon the tips of the chromosomes and non on the life style of a individual.

This implies that if a individual decides to populate a unsafe or unhealthy life style. neither his telomerase nor any alteration on this enzyme will of all time forestall his early decease. The telomerase does non commemorate any being. But this does non intend that the telomerase has no important application. One of the most important applications of telomerase is in the field of oncology. That is. the telomerase has been found to move abnormally during the reproduction of malignant neoplastic disease cells. In normal cells. the action of telomerase ceases right after the chromosomal reproduction.

But in malignant neoplastic disease cells. the telomerase remains active. Scientists assume that there must be some structural difference between the telomerase of normal cells and that of malignant neoplastic disease cells. If the structural difference is found. it might be possible for molecular life scientists to seek out cancerous cells by seeking the telomerase merely. Then. a individual who has malignant neoplastic disease at the early phases can be diagnosed instantly and can use malignant neoplastic disease curative interventions that involve the suppression of the unnatural telomerase ( Shay et al 2001 ) . Decision

The find of the telomerase is one of the most important events in scientific discipline history. It can be considered as critical as the find of the dual spiral construction of the Deoxyribonucleic acid. This is because this enzyme allows the accurate and regulated reproduction of the additive chromosomes of eucaryotes. But. merely as the find of the enzyme was disputing. the constitution of its belongingss and maps are every bit hard to transport out. Yet. molecular life scientists persevere and came up with interesting possible applications of telomerase. Bibliography

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