Ribonucleic acid, messenger

When the cell requires instructions for protein production, part of the code on DNA, starting at an initiator and ending at a stop codon, is converted into a more mobile form by transferring the DNA code into a matching RNA code on a messenger ribonucleic acid (mRNA), a process known as transcription. The decoding, or translation, of mRNA then takes place by special transfer ribonucleic acids (tRNA), which recognize individual codons as amino acids. The sequence of amino acids is assembled into a protein (see Proteins section). In summary, the codes on DNA... 

KhGH A natural, stmctural variant of hGH called 20-K hGH has been reported to occur in the pituitary as well as in the bloodstream (12,13). This variant, which lacks the 15 amino acid residues from Glu-32 to Gln-46, arises from an alternative splicing of the messenger ribonucleic acid (mRNA) (14). This variant shares many but not all of the biological properties of hGH. 

Cellular protein biosynthesis involves the following steps. One strand of double-stranded DNA serves as a template strand for the synthesis of a complementary single-stranded messenger ribonucleic acid (mRNA) in a process called transcription. This mRNA in turn serves as a template to direct the synthesis of the protein in a process called translation. The codons of the mRNA are read sequentially by transfer RNA (tRNA) molecules, which bind specifically to the mRNA via triplets of nucleotides that are complementary to the particular codon, called an anticodon. Protein synthesis occurs on a ribosome, a complex consisting of more than 50 different proteins and several stmctural RNA molecules, which moves along the mRNA and mediates the binding of the tRNA molecules and the formation of the nascent peptide chain. The tRNA molecule carries an activated form of the specific amino acid to the ribosome where it is added to the end of the growing peptide chain. There is at least one tRNA for each amino acid. 

Suda, T Tozawa, F., Iwai, I. et at (1993). Neuropeptide Y increases the corticotropinreleasing factor messenger ribonucleic acid level in the rat hypothalamus. Brain Res. Mol. Brain Res. 18, 311-15. 

Childs, C.V., Lloyd, J.M., Unabia, C., Gharib, S.D., Wierman, M.E., and Chin, W.W. (1987) Detection of luteinizing hormone b messenger ribonucleic acid (RNA) in individual gonadotropes after castration Use of a new in situ hybridization method with a photobiotinylated complementary RNA probe. Mol. Endocrinol. 1, 926-932. 

Garcia T, Lehler S, Bloomer WD, Schachter B (1988) A variant estrogen receptor messenger ribonucleic acid is associated with reduced levels of estrogen binding in human mammary tumors. Mol Endocrinol 2 785... 

Petersen SL, McCrone S, Keller M, Shores S (1995) Effects of estrogen and progesterone on luteinizing hormone-releasing hormone messenger ribonucleic acid levels consideration of temporal and neuroanatomical variables. Endocrinology 136 3604-3610... 

Skynner MJ, Sim JA, Herbison AE (1999) Detection of estrogen receptor a and ft messenger ribonucleic acid in adult gonadotropin-releasing hormone neurons. Endocrinology 140 5195-5201... 

Szabo M, Kilen SM, Nho SJ, Schwartz NB (2000) Progesterone receptor A and B messenger ribonucleic acid levels in the anterior pituitary of rats are regulated by estrogen. Biol Reprod 62 95-102... 

Wilson ME, Price RH, Handa RJ (1998) Estrogen receptor-/ messenger ribonucleic acid expression in the pituitary gland. Endocrinology 139 5151-5156... 

Meso-tetraaryl porphyrins, 14 552 Mesothelioma, 3 316 Messenger ribonucleic acid (mRNA), expression profiling and, 13 354 Messenger RNAs (mRNA), 12 449, 454, 473, 515 17 614, 627 20 824. See also mRNA synthesis... 

Abdelgadir SE, Roselli CE, Choate JV, Resko JA. 1997. Distribution of aromatase cytochrome P450 messenger ribonucleic acid in adult rhesus monkey brains. Biol Reprod 57 ... 

List of Abbreviations cDNA, complementary DNA ddH20, double-distilled H2O dNTP, deoxyribonu-cleotide triphosphate EDTA, ethylenediaminetetraacetic acid MgCl2, magnesium chloride mRNA, messenger ribonucleic acid NaOH, sodium hydroxide PCR, polymerase chain reaction qRT PCR, quantitative reverse transcriptase polymerase chain reaction RNase, ribonuclease RT PCR, reverse transcriptase polymerase chain reaction UTR, untranslated region... 

Ribosomal synthesis of peptides proceeds through translation of messenger ribonucleic acid (mRNA) and utilizes the 20 primary L-a-amino acids. These amino acids are incorporated with the use of specific transfer ribonucleic acid (tRNA) codons. The 20 primary a-amino acids, with the exception of glycine that is achiral, are characterized by an L-configuration at the a-position (Figure 1). In general, most proteins are found to be composed of these 20 L-a-amino acids, as such they are referred to as protein amino acids. 

Yoshida R, Nakajima M, Nishimura K, Tokudome S, Kwon JT, Yokoi T (2003) Effects of polymorphism in promoter region of human CYP2A6 gene (CYP2A6 9) on expression level of messenger ribonucleic acid and enzymatic activity in vivo and in vitro. Clin Pharmacol Ther 74 69-76... 

Sanno, N., Jin, L., Qian, X., Osamura, R. Y., Scheithauer, B. W., Kovacs, K., and Lloyd, R. V. (1997) Gonadotropin-releasing hormone and gonadotropin-releasing hormone receptor messenger ribonucleic acids expression in nontumorous and neoplastic pituitaries. J. Clin. Endocrinol. Metab. 82, 1974-1982. 

Messenger ribonucleic acid (mRNA)—Messenger RNA copy of a gene used to make a protein in a cell it is complementary to and will bind to the DNA gene. 

Ostrowski NL, Lolait SJ, Bradley DJ, O Carroll AM, Brownstein MJ, Young WS (1992) Distribution of Via and V2 vasopressin receptor messenger ribonucleic acids in liver, kidney, pituitary and brain. Endocrinology 131 533-535 Otsuka M, Yoshioka K (1993) Neurotransmitter functions of mammalian tachykinins. Physiol Rev 73 229-308... 

All corticosteroids have the same general mechanism of action they traverse cell membranes and bind to a specific cytoplasmic receptor. The steroid-receptor complex translocates to the cell nucleus, where it attaches to nuclear binding sites and initiates synthesis of messenger ribonucleic acid (mRNA). The novel proteins that are formed may exert a variety of effects on cellular functions. The precise mechanisms whereby the corticosteroids exert their therapeutic benefit in asthma remain unclear, although the benefit is likely to be due to several actions rather than one specific action and is related to their ability to inhibit inflammatory processes. At the molecular level, corticosteroids regulate the transcription of a number of genes, including those for several cytokines. 

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