Rna Synthesis Lab Report

In order to transform deoxyribonucleic acid, DNA, into protein a previous transformation must occur first, and that transformation process is transcription. RNA is similar to DNA; however, DNA has the nitrogenous base thymine while RNA has uracil as a nitrogenous base. RNA and DNA are known to be complementary, being that the two bases pair with each other. Transcription is the synthesis of ribonucleic acid, RNA, using genetic information found within the DNA.

Transcription creates the RNA molecule from the DNA genetic information, and this RNA molecule is known as the messenger ribonucleic acid, mRNA. The mRNA carries a genetic message from the DNA to the protein creating section of the cell. In the first portion of transcription, the enzyme,

RNA polymerase unwinds the DNA double-helix and attaches the complementary parts of RNA onto the strand of DNA that was taken apart and elongated. The section that the enzyme attaches to is where transcription begins, this is known as the promoter. Transcription in eukaryotes requires additional transcription factors to attach to the promoter region and then the DNA strand is able to elongate. The elongation phase is the next stage to occur, and the RNA polymerase travels along the DNA strand and unwinds the double helix a section at a time. During the unwinding of the DNA strand the RNA polymerase unwinds ten to twenty DNA nucleotides at a time in order to pair RNA nucleotides with the strand. When pairing the complementary nucleotides, covalent bonds are being created between the RNA nucleotides and the DNA nucleotides. The final stage of transcription is the termination stage and this particular stage differs between the bacteria cell and eukaryotic cell. The RNA polymerase reaches the termination signal on the DNA strand and all components, DNA, RNA, and RNA polymerase, separate from each other. After the three stages of transcription are completed, the eukaryotic cell must modify the mRNA in order for it to leave the nucleus and enter the cytoplasm where the next process occurs. The post transcription process includes creating a 5’ cap and adds it to the beginning of the strand and the process also creates a 3’ poly-A tail to the end of the mRNA strand. Both of the strand caps are needed in order for the mRNA molecule to leave the nucleus. If the molecule needs more alterations the mRNA can be spliced, the removal of portions of the mRNA molecule.
The bacteria and eukaryotic cell are able to control and regulate the transcription process in order to respond quickly to the surrounding environment. Regulatory proteins are found on DNA and either start or stop the transcription process. Bacterial regulatory proteins have the tendency of stopping transcription, while the eukaryotic regulatory proteins tend to start the transcription process. The bacterial cells have a rapid response to environmental changes and can be almost immediate. An operator controls the access RNA polymerase has to the genes, and it can be found inside of the promoter or could be between the promoter and the enzyme-coding genes. The operator, promoter, and the genes they control make up the operon, which is a transcriptional unit that contains a single regulatory region and multiple coding genes. However, when describing the eukaryotic transcription method of control, there are multiple regulatory regions per gene, which creates a flexible response to the environment and allows for the creation of multiple proteins from one gene. Within eukaryotic cells, the changes made are in response to developmental phases of life such as, eggs, larvae, pupa, and adult life phases. In eukaryotes, control elements regulate transcription by binding transcription factors. Eukaryotic cells need the transcription factors in order to initiate transcription and the binding of the transcription factors serves as a way of regulating and/or controlling transcription.
The main differences between the bacterial cells and the eukaryotic cells, when describing transcription, is the obvious fact that bacteria do not have nuclei and this absence of compartmentalization allows transcription and translation to occur simultaneously.

Transcription occurs within the cytoplasm, and translation also occurs in the cytoplasm within the bacterial cell. However, within the eukaryotic cell the process of transcription occurs within the nucleus and translation occurs within the cytoplasm. The separation of the two processes is due to the fact that the nucleus is where DNA is contained in the eukaryotic cell, and the process of transcription changes the state of mRNA in order to escort the pre mRNA out of the nucleus and into the cytoplasm. During the initiation stage of transcription, the eukaryotic cells have a slightly more complex process. Eukaryotes require multiple transcription factors to bind to the DNA before the RNA polymerase II can attach. The attachment of the multiple transcription factors and the RNA polymerase II enzyme creates the transcription initiation complex, none of which occurs within the bacterial cell. After the transcription process, the eukaryotic cells requires some alteration to the mRNA strand in order to escort it out of the nucleus and into the cytoplasm. The addition of the 5’ cap and the 3’ cap is necessary in order to exit the nucleus; however, none the post-transcription modifications are needed for the bacterial cells. This is due to the previously stated reason of the eukaryotic cell having compartmentalization within the cell, while the bacterial cells have no nucleus holding the cell’s

DNA.
In conclusion, the transcription process includes the three stages initiation, elongation, and termination. Transcription is the transformation of genetic material, DNA, into the messenger RNA molecule, which can proceed into another process known as translation. Eukaryotes differ from the bacterial cells at various points within the transcription process, but the overall procedure is the same. The end result of both transcription processes is the messenger RNA that will later go on into translation.