Ribonucleic acid polymerase synthesis

Roeder, R. G. and Rutter, W. J., Multiple ribonucleic acid polymerases and ribonucleic acid synthesis during sea urchin development, Biochemistry, 9,2543, 1970. 

Stirpe, F. and Fiume, L. Studies on the pathogenesis of liver necrosis by a-amanitin. Effect of a-amanitin on ribonucleic acid synthesis and on ribonucleic acid polymerase in mouse liver nuclei. Biochem. J., 105, 779-782 (1967)... 

Fox, C. F., Robinson, W. S., Haselkorn, R., Weiss, S. B. Enzymatic synthesis of ribonucleic acid. III. The ribonucleic acid-primed synthesis of ribonucleic acid with Micrococcus lysodeikticus ribonucleic acid polymerase. J. biol. Chem. 239, 186-193 (1964). 

The aminoacyl transfer reaction, one of the latter stages in protein synthesis, involves incorporation of amino acids from soluble ribonucleic acid-amino acid into ribosomal protein. This reaction requires guanosine triphosphate and a soluble portion of the cell. Evidence has been obtained with rat liver preparations that aminoacyl transfer is catalyzed by two protein factors, aminoacyl transferases (or polymerases) I and n, which have been resolved and partially purified from the soluble fraction. Transferase n activity has also been obtained from deoxycholate-soluble extracts of microsomes. With purified transferases I and n, incorporation is observed with relatively low levels of GTP its sulfhy-dryl requirement is met by a variety of compounds. The characteristics of this purified amino acid incorporating system, in terms of dependency on the concentration of its components, are described. 

Baltimore D, Huang AS, Stampfer M (1970) Ribonucleic acid synthesis of vesicular stomadds virus, II. An RNA polymerase in the virion. Proc Natl Acad Sci USA 66 572-576. 

Rickets, 482,483,575,576, 582,583, 584 Rislt ratio, 908, 965-%6,968 RMR, see Resting iretabolic rate RNA (ribonucleic acid), 12 cellular function, 32 chetnical structure, 13 structure, 937 synthesis, 13,16 RNA polymerase, 33-35 RNasas, 122 Rods, 561,563-564 rRNA (ribosomal RNA), 34 Rubidium, 703... 

When not replicating, DNA serves as the code for synthesis of proteins. During protein synthesis, a small portion of DNA is copied by complementary base pairing of RNA nucleotides (adenine, guanine, cytosine and uracil instead of thymine) to form single stranded messenger ribonucleic acid (mRNA) in the nucleus of the cell. This process is known as transcription and is catalysed by an enzyme called RNA polymerase. 

RNA polymarata, DNA-dependent RNA polymerase, nucleoside trlphosphate RNA nucleotidyltransferase, transcriptase (EC 2.7.7.6) an enzyme which cataiyses the synthesis of RNA on a DNA template. The base sequence of the resulting RNA is compiementary to that of the DNA template (see Ribonucleic acid). 

The information which specifies the amino-acid sequence of a protein is stored in the nucleotide sequence of the double helix of deoxyribonucleic acid (DNA). The transcription of sections of this information into ribonucleic acid (RNA) is catalysed by RNA polymerases. These enzymes not only control the synthesis of RNA but also recognize stop and start signals on the DNA. The start signals are complex and may be blocked by repressor molecules which inhibit the transcription process. Once synthesized, the (messenger) RNA is processed and exported to ribosomes where its nucleotide sequence is translated into protein. Triplets of three nucleotides (codons) in the messenger RNA each specify (encode) one amino acid. The linear sequence of nucleotides in the messenger RNA thus specifies the sequence of amino acids in the protein whose primary structure will therefore correspond directly to the sequence of nucleotides in the DNA. 

Amanita toxins (amataxkis) are cyclic octapeptides that reduce protein synthesis by inhibiting ribonucleic acid (RN polymerase and transcription. 

For all forms of DNA, hydrogen bonding between the two spiral chains stabilizes the double helix. Replication of DNA occurs when the hydrogen bonds are broken, and the two strands are separated. These form the templates that are used to make identical copies, via enzymes called DNA polymerases. In fact, the second strand of the double helix is complementary to the first, it contains no extra information but is involved in replication. Ribonucleic acid (RNA) is also found in cells. It has a similar structure to DNA, but the sugar is instead D-ribose and uracil bases replace thymine bases. RNA is important in the synthesis of proteins. It is produced from DNA templates via the process of transcription. Further details of protein biochemistry can be found elsewhere (e.g. Voet and Voet, 1995). Here we simply emphasize that life itself is created from that special class of soft material called polymers. 

Stetler, D. A., and Rose, K. M., 1982, Phosphorylation of deoxyribonucleic acid dependent RNA polymerase II by nuclear protein kinase Nil Mechanism of enhanced ribonucleic acid synthesis. Biochemistry 21 3721-3728. 

Necrosis is often initiated by damage to membranes, either the plasma membrane of the cell or the membranes of organelles, particularly mitochondria (Zimmerman, 1999). Cell membrane damage is often caused by membrane phospholipid peroxidation. Plasma membrane damage interferes wi ion regulation, calcium homeostasis, energy production, and decrease in the ability of that organelle to sequester calcium. Inhibition of protein synthesis is an alternative mechanism that may cause cell necrosis. Toxins that act in this way include phalloidin and related mushroom toxins, which inhibit the action of ribonucleic acid (RNA) polymerase, and therefore mRNA synthesis (Pineiro-Carrero and Pineiro, 2004). 

In like manner, ribosomal ribonucleic acid (rRNA) and transfer ribonucleic acid (tRNA) are synthesized from their specific genes through the action of DNA-dependent RNA polymerase. And as in the case of mRNA, each of the precursor forms of these nucleotides are also processed until they reach their final forms. The rRNAs and a large variety of ribosomal proteins are assembled to form the ribosome. Ribosomes, the supramolecular structures in which protein synthesis takes place and which functionally resemble multienzyme complexes, are elaborate structures. They are attached, by a binding site on the smaller subribosomal particle, to the endoplasmic reticulum. The tRNAs that are synthesized finally become charged with specific amino acids. 

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