Ribonucleic acid RNA polymerase

Drug X is an ami mycobacterial agent that inhibits other bacteria as well as poxviruses. However, it should not be used as a single agent because resistant mutants frequently form. The responsible mutation may alter the site of action of drug X [i.e., the deoxyribonucleic acid (DNA)-dependent ribonucleic acid (RNA) polymerase]. What is drug X ... 

Okazaki fragment Short segments of DNA (approximately 1000 nucleotides in prokaryotes, 100 to 200 nucleotides in eukaryotes) synthesized on the lagging strand during DNA replication. As the replication fork opens, the ribonucleic acid (RNA) polymerase primase synthesizes a short RNA primer, which is extended by DNA polymerase until it reaches the... 

Deoxyribonucleic acid (DNA) and ribonucleic acid (RNA) polymerases have been separated and purified on DNA-glass columns, effecting more rapid purification than affinity chromatography on DNA-cellulose (21,22). The DNA is coupled... 

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). 

Ribonucleic Acid Ribonucleic acid (RNA) is a polymer consisting of nucleotides containing ribose and four different nucleotides adenine, guanine, cytosine, and uracil. Three main classes of RNA molecules are transcribed from DNA by three different types of RNA polymerases mRNA, tRNA and rRNA. Other RNA types are found in very small amounts including snRNAs, double-stranded RNA (dsRNA) and other non-coding RNAs such as the SRP RNAs. All RNA classes present in cells serve different functions. 

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. 

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. 

Ribonucleic acid (RNA) is the other major nucleic acid besides DNA, but unlike DNA, it is single stranded. It contains ribose instead of deoxyribose as its sugar—phosphate backbone and uracil (U) instead of thymine (T) in its pyrimidine bases (Nilsson et al., 2015). Like DNA, BJSIA can be assembled from nucleotides using DNA sequence as a template and RNA polymerase. The structure of an RNA molecule is also determined by its... 

List of Abbreviations PCR, polymerase chain reaction RT-PCR, reverse transcription polymerase chain reaction DNA, deoxyribonucleic acid RNA, ribonucleic acid RNase, ribonuclease mRNA, messenger RNA GABAa, y-aminobutyric acid type A cRNA, copy RNA dNTPs, deoxy nucleoside triphosphates MMLV, Mouse Moloney murine leukemia vims RT, reverse transcriptase bp, base pair Tm, melting temperature DEPC, diethylpyrocarbonate OD, optical density mL, milliliter SA-PMPs, streptavidin paramagnetic particles dT, deoxy thymidine DTT, dithiothreitol DNase, deoxyribonuclease RNasin, ribonuclease inhibitor UV, ultraviolet TBE, Tris-borate, 1 mM EDTA EDTA, ethylenediaminetetraacetic acid Buffer RET, guanidium thiocyanate lysis buffer PBS, phosphate buffered saline NT2, Ntera 2 neural progenitor cells... 

For reduplication, the chains are separated and on each a new, complementary strand is synthesized by enzymes called DNA polymerases [652J. For protein biosynthesis, the DNA is copied (transcribed) into the messenger ribonucleic acid (mRNA) by the enzyme RNA polymerase (Fig. 20.2) where, in contrast to DNA, the deoxyribose is replaced by ribose and thymine by the equivalent uracil. Here again, the Watson-Crick base pair plays the crucial role so that the mRNA sequence is complementary to the DNA sequence. 

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. 

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