![]() ![]() This confirms that both daughters’ cells have precisely similar genetic material. It can be said that the duplication of DNA is crucial before the cell division, wherein one parent cell can divide to form two daughter cells. Thus, this permits for the replication of two, continuous identical daughter strands of DNA. This is achieved by the enzyme DNA ligase, which seals the sugar-phosphate backbone of the Okazaki fragments. The Okazaki fragments must be attached together into one continuous strand after replication. Once both leading and lagging strands have been completed, another type of DNA polymerase, DNA polymerase I, comes in and gets rid of the RNA primers and substitutes them with DNA. One significant role that Okazaki fragments play is in enabling the DNA polymerase to synthesise the lagging strand in spite of it being concerned with the opposite direction. This prerequisite has two essential significances:ġ – The lagging strand must have advanced priming and fragment connection mechanisms including several supplementary steps and reactions than needed for leading-strand extension.Ģ – The Mechanisms of lagging-strand replication must have developed means of avoiding mutagenesis while managing the essential strand handlings. The strand is synthesised in short segments and it is known as Okazaki fragments, named after its discoverers, the segments are later joined. This can only be achieved if the strand is completed discontinuously. On the other hand, the lagging strand must be intermittently extended away from the opening helix. The leading strand can easily be extended in an unceasing way in a similar way as the helix must open to permit exposure of templates for polymerization. This is since DNA synthesis can continue only in a single direction - the 5′ to 3′ direction. Okazaki fragments are the ones that are later associated covalently to form a continuous strand. Contrasting to the leading strand wherein the DNA can be created continuously the lagging strand is synthesised discontinuously in the form of short fragments called Okazaki fragments. The leading strand is the one that goes from 5’ to 3′ whereas the lagging strand is the one that goes from 3′ to 5′. Therefore, this is known as the replication fork. Formation of Okazaki Fragmentsĭuring the initial phase of DNA replication, the DNA winds down and the two components of DNA split in two leading to the formation of two prongs that bear a resemblance to a fork. Thus, Okazaki fragments are named after its discoverers Reiji Okazaki and his spouse, Tsuneko Okazaki. Reiji Okazaki, Tsuneko Okazaki, along with their colleagues initially discovered the Okazaki fragments whilst they were studying the duplication of bacteriophage DNA in Escherichia coli in 1968. Thus, it can be said that Okazaki fragments are comparatively petite fragments of DNA that are synthesised on the lagging strand at the time of DNA replication. Okazaki fragments can be described as those fragments of DNA which are temporary components of lagging DNA combinations at the replication fork.
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