Polyadenylic acid poly

Until recently 1 3C nmr studies of nucleic acids have not received the same attention as those of nucleosides and nucleotides. Poly-uridylic acid (poly U), polyadenylic acid (Poly ), and unfractionated baker s yeast transfer ribonucleic acid (tRNA) have been investigated by 13C nmr techniques (Table 11 Mantsch and Smith, 1972 Komoroski and Allerhand, 1972, 1974). Assignments for uridine monophosphates were based on changes in phosphorus-carbon splittings and on changes in the chemical shift of approximately 2-5 ppm on the phosphorylated carbon, which was caused by the deshielding effect of the phosphate group (Mantsch and Smith,... 

Miles (1960) has shown spectra of the three-stranded helices formed between polyadenylic acid (poly A) and polyuridylic acid (poly U) and between poly U and tetra A (tetraadenylic acid, pApApApA). For the related spectra, the assignment of bands, and the experimental methods used, some of Miles s previous papers (1956 1958a,b 1959) should be consulted. The infrared spectra of the double helix formed... 

Since the discovery by Hadjivassiliou and Brawerman (1966) that rat liver microsomes contain polyadenylic acid [poly(A)] sequences, there has been much recent evidence which indicates that a high proportion of the messenger RNA s (mRNA s) of mammalian cells contain poly(A) sequences which are covalently linked to the mRNA molecule. Most of the rapidly labeled nonribosomal RNA components of mouse sarcoma 180, HeLa, and L cell polysomes have been shown to contain adenylate-rich sequences (Lee et at, 1971 Edmonds et al., 1971 Darnell et at, 1971a Sheldon et at, 1972 Perry et al., 1972). 

Similar experiments were carried out with different synthetic polyribonucleotides. It was found, for example, that polyadenylic acid (poly A) leads to the synthesis of polylysine, and that polycytidylic acid (poly C) leads to the synthesis of polyproline. By 1964, all 64 codons had been deciphered (Table 20.4). Nirenberg, R. W. Holley, and H. G. Khorana shared the 1968 Nobel Prize in Physiology or Medicine for their seminal work. 

Figure 9.9 CD spectrum of adenylic acid, polyadenylic acid [poly (All and denatured poly (A). Explanation in the text.

Abbreviations DNA deoxyribonucleic acid RNA ribonucleic acid rRNA ribosomal RNA tRNA transfer RNA. A adenine U uracil G guanine C cytosine, poly A polyadenylic acid poly U polyuridylic acid poly C polycytidylic acid poly I poly-inosinic acid poly G polyguanylic acid. The letters r and d refer to the ribose or deoxy-ribose series. Complexes between the polynucleotides are written as follows polyG poly C double-stranded helical complex of poly G and poly C 2 poly G poly C, triple-stranded complex. BSA bovine serum albumin MBSA methylated bovine serum albumin. N nitrogen. AMV Avian myeloblastosis virus NDV Newcastle disease virus. SLE systemic lupus erythematosus. 

Table 5.24. 13C Chemical Shifts (6C in ppm) of Randomly Coiled Poly(8-bromoadenylic Acid), Polyadenylic Acid and Corresponding 5 -Mononucleotides Temperature 70 °C Solvent D2Q, pD 7.0-7.3 [781],...

Growing membrane systems have been used to obtain artificial infrabiological systems. Walde et al. [47] have carried out the synthesis of polyadenylic acid in self-reproducing vesicles [48], in which the enzyme polynucleotide phosphorylase carried out the synthesis of poly-A, and membrane vesicle multiplication was due to the hydrolysis of externally provided oleic anhydride to oleic acid. The snag is that the enzyme component is not auto-catalytic. Enzymatic RNA replication in vesicles [49] suffers from the same problem. It is also not known whether redistribution of the entrapped enzymes into newly formed vesicles occurs or not. An affirmative answer would be evidence for vesicle reproduction by fission. 

Poly A Sepharose Polyadenylic acid mRNA-binding proteins Viral RNA, RNA polymerase Pharmacia... 

RNA and synthetic polyribonucleotides that, like RNA, contain ribose as the sugar component but, unlike RNA, contain only one of the four bases in a polymeric chain (e.g., polyadenylic acid, or poly A). 

This reaction was reported for the benzophenone photosensitized degradation of polypropylene (92),polystyrene (95), poly(vinyl alcohol) (94),polyisoprene (95,96),polyurethane (97) and polyadenylic acid (98) In solid state benzophenone also produce an extensive crosslinking of polyethylene (99-105) It has also been found that benzophenone and its derivatives caused an initial rapid oxidation,increasing with ketone concentration (70) Currently the relative importance of singlet oxygen formation in energy transfer reaction between excited benzophenone and molecular oxygen is discussed (92,104) ... 

Oparin and coworkers [125,126] have studied the enzymic polymerization of ADP by polynucleotide phosphorylase (PNPase) and Mg ions in coacervates in an attempt to construct primitive forms of precellular structures. Walde et al. [127] have investigated this enzymic ADP polymerization in AOT reversed micellar solutions instead of coacervates. The PNPase-catalyzed synthesis of poly(A) (polyadenylic acid) in the AOT reversed micelles was carried out by mixing two reversed micellar solutions, one containing ADP and the other containing the enzyme. 

Poly A polyinerase an enzyme which spedfically catalyses the synthesis of poly A sequences, a process which does not require DNA. P. from calf thymus has M, about 150,000. It is localized in the nucleus, and is responsible for the covalent attachment of poly A sequences to RNA (see Polyadenylic acid). 

The addition of a sequence of polyadenylic acid residues (poly A) to newly synthesized mRNAs appears to be a necessary step for their activation prior... 

Fig. 11. Temperature dependence of the P chemical shift of the double-helix signal of the 1 1 mixture of oligouiidylic acid [oIigo(U)] and polyadenylic add (poly(A)] (O, —) and P signals of yeast phenylalanine-tRNA (—). For poly(A) oligo(U) sample pH 7, 20% D2O, 0.2 NaCl, 10 mMcacodylate, 1 mil/EDTA. 24 mg/ml total nucleotide. For tRNA 0.1 M NaQ, 10 mM cacodylate, 10 mMMgQ2,1 mAf EDTA, 10-20% D2O, pH 7. From Gorenstein, et al. (1982). Copyright 1982 American Chemical Sodety.

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