Messenger RNA and

If an antibody to the protein of interest is available, it is sometimes possible to use vector sequences, eg, the beta-galactosidase promoter sequence, to direct the transcription of the passenger DNA into messenger RNA and the translation of that mRNA into protein which can be recognized by the antibody. Although this method is somewhat less reHable than the use of nucleic acid probes, specialized vectors are available for this purpose. 

Yla-Herttuala, S., Rosenfeld, M.E., Parthasarathy, S., Glass, C.R., Sigal, E., Witztum, J.L. and Steinberg, D. (1990). Colocalisation of 15-lipoxygenase messenger RNA and protein with epitopes of oxidised low density lipoprotein in macrophage-rich areas of atherosclerotic lesion. Proc. Natl Acad. Sci. USA, 87, 6959-6963. 

Little K., McLaughlin D., Zhang L. et al. Brain dopamine transporter messenger RNA and binding sites in cocaine users. Arch. Gen. Psychiatry. 55 793, 1998. 

A primer is a very special sequence, which plays an important role in duplication, (i) In RNA, it is a short sequence that is paired with one strand of DNA and provides a free 3 -OH terminus at which a DNA polymerase starts synthesis of a deoxyribonucleotide chain, (ii) In DNA, it is another short sequence, which is complementary to a sequence of messenger RNA and allows reverse transcriptase to start copying the adjacent sequences of mRNA. (iii) In retroviruses, it is a cellular transfer RNA whose elongation initiates RNA-directed DNA synthesis by the DNA polymerase. 

The answer is e. (Katzung, p 842.) Ribavirin most likely interferes with guanosine triphosphate synthesis, resulting in inhibition of capping of viral messenger RNA and viral RN A-dependent RNA polymerase. It is effective in moderating infections with respiratory syncytial virus. 

Phelps CF, Amstein HRV. Messenger RNA and Ribosomes in Protein Synthesis, Biochemical Society, London, UK, 1982. 

Gurdon IB, Lane CD, Woodland HR, Marbaix G. 1971. Use of frog eggs and oocytes for the study of messenger RNA and its translation in living cells. Nature. 233 177. 

There are three classes of RNA ribosomal RNA, messenger RNA, and transfer RNA. It is messenger RNA that codes for the structure of proteins. 

Korte J.J, M.D. Kahl, K.M. Jensen, M.S. Pasha, L.G. Parks, G.A. LeBlanc, and G.T. Ankley (2000). Fathead minnow vitellogenin Complementary DNA sequence and messenger RNA and protein expression after 17 3-estradiol treatment. Environmental Toxicology and Chemistry 19 972-981. 

Mechanism of Action Clioquinol is a broad-spectrum antibacterial agent but the mechanism of action is unknown. Hydrocortisone is a corticosteroid that diffuses across cell membranes, forms complexes with specific receptors and further binds to DNA and stimulates transcription of mRNA (messenger RNA) and subsequent protein synthesis of various enzymes thought to be ultimately responsible for the anti-inflammatory effects of corticosteroids applied topically to the skin Therapeutic Effect Alters membrane function and produces antibacterial activity Pharmacokinetics Clioquinol may be absorbed through the skin in sufficient amounts. 

Saito N, Guitart X, Hayward M, et al Corticosterone differentially regulates the expression of G a and Gja messenger RNA and protein in rat cerebral cortex. Proc Natl Acad Sci U S A 86 3906-3910, 1989... 

This revolution in our understanding of the structure of DNA inevitably stimulated questions about its function. The double-helical structure itself clearly suggested how DNA might be copied so that the information it contains can be transmitted from one generation to the next. Clarification of how the information in DNA is converted into functional proteins came with the discovery of both messenger RNA and transfer RNA and with the deciphering of the genetic code. 

Figure 25-28 Peptide-bond formation in protein biosynthesis showing how the amino-acid sequence is determined by complementary basepairing between messenger RNA and transfer RNA, The peptide chain is bound to tRNA, which is associated with mRNA through three bases in mRNA (codon) and three bases in tRNA (anticodon). In the diagram, the next codon A-A-G codes for lysine. Hence, Lys-tRNA associates with mRNA by codon-anticodon base-pairing and, under enzyme control, couples to the end of the peptide chain.

Overview of reactions in protein synthesis. (aab aa2, aa3 = amino acids l, 2, 3.) Protein synthesis requires transfer RNAs for each amino acid, ribosomes, messenger RNA, and a number of dissociable protein factors in addition to ATP, GTP, and divalent cations. First the transfer RNAs become charged with amino acids, then the initiation complex is formed. Peptide synthesis does not start until the second aminoacyl tRNA becomes bound to the ribosome. Elongation reactions involve peptide bond formation, dissociation of the discharged tRNA, and translocation. The elongation process is repeated many times until the termination codon is reached. Termination is marked by the dissociation of the messenger RNA... 

The genetic code is the sequence relationship between nucleotides in the messenger RNA and amino acids in the proteins they encode. Triplet codons are arranged on the messenger in a nonoverlapping manner without spacers. 

Initiation factors contribute to the ribosome complex with the messenger RNA and the initiator methionyl-tRNA. Elongation factors assist the binding of all the other tRNAs and the translocation reaction that must occur after each peptide bond is made. Termination factors recognize a stop signal and lead to the termination of polypeptide synthesis and the release of the polypeptide chain and the messenger from the ribosome. 

Humpel C., Lippoldt A., Chadi G., Ganten D., Olson L., and Fuxe K. (1993). Fast and widespread increase of basic fibroblast growth factor messenger RNA and protein in the forebrain after kainate-induced seizures. Neuroscience 57 913-922. 

Hosokawa M., Klegeris A., Maguire J., and McGeer P. L. (2003). Expression of complement messenger RNAs and proteins by human oligodendroglial cells. Glia 42 417 123. 

Although its mechanism of action has not been fully elucidated, it appears to interfere with the synthesis of guanosine triphosphate, to inhibit capping of viral messenger RNA, and to inhibit the viral RNA-dependent RNA polymerase of certain viruses. Ribavirin triphosphate inhibits the... 

Messenger RNA and Transfer RNA Messenger RNA (m-RNA) is synthesized in the nucleus directly from DNA. Its job is to carry the instructions coded on the DNA out into the cytoplasm, where protein synthesis will occur. While m-RNA can adopt more complicated structures, we can think about m-RNA as a simple, straight chain of nucleotides. 

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