Messenger RNA processing

Proudfoot, N. (2000). Connecting transcription to messenger RNA processing. Trends Biochem. Sri. 25(6), 290-293. 

Messenger RNA processing/modification. Most primary mRNA transcripts in prokaryotes function in translation without further modification. Eukaryotic mRNA transcripts, however, undergo extensive posttranscriptional modifications. 

Key words Messenger RNA processing, Pre-mRNA 3 -end formation. Cleavage and polyadenylation. 

Stinton, L. M., Eystathioy, T., Selak, S., Chan, E. K., and Fritzler, M. J. (2004). Autoantibodies to protein transport and messenger RNA processing pathways Endosomes, lysosomes, Golgi complex, proteasomes, assemblyosomes, exosomes, and GW bodies. Clin. Immunol. 110, 30-44. 

Messenger RNA (mRNA) is the intermediate template between DNA and proteins. The information from a particular gene is transferred from a strand of DNA by the construction of a complementary strand of RNA through a process known as transcription. The amount of any particular type of mRNA in a cell reflects the extent to which a gene has been expressed . 

Some RNA molecules have intrinsic catalytic activity. The activity of these ribozymes often involves the cleavage of a nucleic acid. An example is the role of RNA in catalyzing the processing of the primary transcript of a gene into mature messenger RNA. 

Enzymes in viruses We have stated that virus particles do not carry out metabolic processes. Outside of a host cell, a virus particle is metabolically inert. However, some viruses do contain enzymes which play roles in the infectious process. For instance, many viruses contain their own nucleic acid polymerases which transcribe the viral nucleic acid into messenger RNA once the infection process has begun. The retroviruses are RNA viruses which replicate inside the cell as DNA intermediates. These viruses possess an enzyme, an RNA-dependent DNA popo called reverse transcriptase, which transcribes the information in the incoming RNA into a DNA intermediate. It should be noted that reverse transcriptase is unique to the retroviruses and is not found in any other viruses or in cells. 

Bacteria, being procaryotic, do not show compartmentation of the biosynthetic processes. The genome of a bacterium relates directly to the cytoplasm of the cell. Transcription into mRNA can lead directly to translation, and the processes of transcription and translation are not carried out in separate organelles. Animal cells, being eucaryotic, show compartmentation of the transcription and translation processes. Transcription of the genome into mRNA occurs in the nucleus, whereas translation occurs in the cytoplasm. The messenger RNA in the eucaryote is usually modified by adding to it... 

Ribonucleic acid (RNA) Molecules including messenger RNA, transfer RNA, ribosomal RNA, or small RNA. RNA serves as a template for protein synthesis and other biochemical processes of the cell. The structure of RNA is similar to that of DNA except for the base thymidine being replaced by uracil. 

Sheth, U., and Parker, R. (2003). Decapping and decay of messenger RNA occur in cytoplasmic processing bodies. Science 300, 805—808. 

Current hypotheses indicate that B-cell transcriptional processes are disrupted, which prevent expression of B-cell surface markers and production of immunoglobulin messenger RNA. Alterations in the normal apoptotic pathways favor cell survival and proliferation. 

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