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RNA

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Image:Pre-mRNA-1ysv.png
A hairpin loop from a pre-mRNA. Notice its nitrogen-rich (blue) bases and oxygen-rich (red) backbone.

Ribonucleic acid or RNA is a nucleic acid made from a long chain of nucleotide units. Each nucleotide consists of a nitrogenous base, a ribose sugar, and a phosphate. RNA is very similar to DNA, but differs in a few important structural details: in the cell RNA is usually single stranded, while DNA is usually double stranded. RNA nucleotides contain ribose while DNA contains deoxyribose (a type of ribose that lacks one oxygen atom), and in RNA the nucleotide uracil substitutes for thymine, which is present in DNA.

RNA is transcribed from DNA by enzymes called RNA polymerases and is generally further processed by other enzymes. Some of these RNA-processing enzymes contain RNA as part of their structures. RNA is also central to the translation of some RNAs into proteins. In this process, a type of RNA called messenger RNA carries information from DNA to structures called ribosomes. These ribosomes are made from proteins and ribosomal RNAs, which come together to form a molecular machine that can and read messenger RNAs and translate the information they carry into proteins. It has also been known since the 1990s that several types of RNA regulate which genes are active.

Contents

Structure

Image:Piwi-siRNA-basepairing.png
Watson-Crick base pairs in a siRNA (hydrogen atoms are not shown)

Each nucleotide in RNA contains a ribose sugar, with carbons numbered 1' through 5'. A base is attached to the 1' position, generally adenine (A), cytosine (C), guanine (G) or uracil (U). A phosphate group is attached to the 3' position of one ribose and the 5' position of the next. The phosphate groups have a negative charge each at physiological pH, making RNA a charged molecule (polyanion). The bases may form hydrogen bonds between cytosine and guanine, between adenine and uracil and between guanine and uracil.[1] However other interactions are possible, such as a group of adenine bases binding to each other in a bulge,[2] or the GNRA tetraloop that has a guanine–adenine base-pair.[1]

Image:RNA chemical structure.GIF
Chemical structure of RNA

An important structural feature of RNA that distinguishes it from DNA is the presence of a hydroxyl group at the 2' position of the ribose sugar. The presence of this functional group enforces the C3'-endo sugar conformation (as opposed to the C2'-endo conformation of the deoxyribose sugar in DNA) that causes the helix to adopt the A-form geometry rather than the B-form most commonly observed in DNA.[3] This results in a very deep and narrow major groove and a shallow and wide minor groove.[4] A second consequence of the presence of the 2'-hydroxyl group is that in conformationally flexible regions of an RNA molecule (that is, not involved in formation of a double helix), it can chemically attack the adjacent phosphodiester bond to cleave the backbone.[5]

RNA is transcribed with only four bases (adenine, cytosine, guanine and uracil),[6] but there are numerous modified bases and sugars in mature RNAs. Pseudouridine (Ψ), in which the linkage between uracil and ribose is changed from a C–N bond to a C–C bond, and ribothymidine (T), are found in various places (most notably in the TΨC loop of tRNA).[7] Another notable modified base is hypoxanthine, a deaminated guanine base whose nucleoside is called inosine. Inosine plays a key role in the wobble hypothesis of the genetic code.[8] There are nearly 100 other naturally occurring modified nucleosides,[9] of which pseudouridine and nucleosides with 2'-O-methylribose are the most common.[10] The specific roles of many of these modifications in RNA are not fully understood. However, it is notable that in ribosomal RNA, many of the post-transcriptional modifications occur in highly functional regions, such as the peptidyl transferase center and the subunit interface, implying that they are important for normal function.[11]

Image:Ciliate telomerase RNA.JPG
Secondary structure of an RNA from a telomerase

The functional form of single stranded RNA molecules, just like proteins, frequently requires a specific tertiary structure. The scaffold for this structure is provided by secondary structural elements which are hydrogen bonds within the molecule. This leads to several recognizable "domains" of secondary structure like hairpin loops, bulges and internal loops.[12] There has been a significant amount of research directed at the RNA structure prediction problem.

Comparison with DNA

RNA and DNA differ in three main ways. First, unlike DNA which is double-stranded, RNA is a single-stranded molecule in most of its biological roles and has a much shorter chain of nucleotides. Second, while DNA contains deoxyribose, RNA contains ribose, (there is no hydroxyl group attached to the pentose ring in the 2' position in DNA, whereas RNA has two hydroxyl groups). These hydroxyl groups make RNA less stable than DNA because it is more prone to hydrolysis. Third, the complementary nucleotide to adenine is not thymine, as it is in DNA, but rather uracil, which is an unmethylated form of thymine.[13]

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convert: missing an image filename `/home/www/en.wikilib.com/images/thumb/d/d7/Ribosome_50s.png/180px-Ribosome_50s.png'.
The 50S ribosomal subunit. RNA is in orange, protein in blue. The active site is in the middle (red).

Like DNA, most biologically active RNAs including tRNA, rRNA, snRNAs and other non-coding RNAs are extensively base paired to form double stranded helices. Structural analysis of these RNAs have revealed that they are highly structured. Unlike DNA, this structure is not long double-stranded helices but rather collections of short helices packed together into structures akin to proteins. In this fashion, RNAs can achieve chemical catalysis, like enzymes.[14] For instance, determination of the structure of the ribosome—an enzyme that catalyzes peptide bond formation—revealed that its active site is composed entirely of RNA.[15]

Synthesis

Synthesis of RNA is usually catalyzed by an enzyme—RNA polymerase—using DNA as a template. Initiation of synthesis begins with the binding of the enzyme to a promoter sequence in the DNA (usually found "upstream" of a gene). The DNA double helix is unwound by the helicase activity of the enzyme. The enzyme then progresses along the template strand in the 3’ to 5’ direction, synthesizing a complementary RNA molecule with elongation occurring in the 5’ to 3’ direction. The DNA sequence also dictates where termination of RNA synthesis will occur.[16]

There are also a number of RNA-dependent RNA polymerases as well that use RNA as their template for synthesis of a new strand of RNA. For instance, a number of RNA viruses (such as poliovirus) use this type of enzyme to replicate their genetic material.[17] Also, it is known that RNA-dependent RNA polymerases are required for the RNA interference pathway in many organisms.[18]

Types of RNA

Overview

Image:Full length hammerhead ribozyme.png
Structure of a hammerhead ribozyme, a ribozyme that cuts RNA

Messenger RNA (mRNA) is the RNA that carries information from DNA to the ribosome sites of protein synthesis (translation) in the cell. The coding sequence of the mRNA determines the amino acid sequence in the protein that is produced.[19]

RNA genes are genes that encode RNA which is not translated into a protein, known as non-coding RNA or small RNA. Non-coding RNAs can also derive from introns.[20] The most prominent examples of non-coding RNAs are transfer RNA (tRNA) and ribosomal RNA (rRNA), both of which are involved in the process of translation.[13] There are also non-coding RNAs involved in gene regulation, RNA processing and other roles. Certain RNAs are able to catalyse chemical reactions such as cutting and ligating other RNA molecules,[21] and the catalysis of peptide bond formation in the ribosome;[15] these are known as ribozymes.

Double-stranded RNA (dsRNA) is RNA with two complementary strands, similar to the DNA found in all cells. dsRNA forms the genetic material of some viruses (double-stranded RNA viruses). In eukaryotes, long double-stranded RNA such as viral RNA can trigger RNA interference, where short dsRNA molecules called siRNAs (small interfering RNAs) can silence the expression of genes.[22]

In translation

Messenger RNA (mRNA) carries information about a protein sequence to the ribosomes, the protein synthesis factories in the cell. It is coded so that every three nucleotides (a codon) correspond to one amino acid. In eukaryotic cells, once precursor mRNA (pre-mRNA) has been transcribed from DNA, it is processed to mature mRNA. This removes its introns—non-coding sections of the pre-mRNA. The mRNA is then exported from the nucleus to the cytoplasm, where it is bound to ribosomes and translated into its corresponding protein form with the help of tRNA. In prokaryotic cells, which do not have nucleus and cytoplasm compartments, mRNA can bind to ribosomes while it is being transcribed from DNA. After a certain amount of time the message degrades into its component nucleotides with the assistance of ribonucleases.[19]

Transfer RNA (tRNA) is a small RNA chain of about 80 nucleotides that transfers a specific amino acid to a growing polypeptide chain at the ribosomal site of protein synthesis during translation. It has sites for amino acid attachment and an anticodon region for codon recognition that binds to a specific sequence on the messenger RNA chain through hydrogen bonding.[20]

Ribosomal RNA (rRNA) is the catalytic component of the ribosomes. Eukaryotic ribosomes contain four different rRNA molecules: 18S, 5.8S, 28S and 5S rRNA. Three of the rRNA molecules are synthesized in the nucleolus, and one is synthesized elsewhere. In the cytoplasm, ribosomal RNA and protein combine to form a nucleoprotein called a ribosome. The ribosome binds mRNA and carries out protein synthesis. Several ribosomes may be attached to a single mRNA at any time.[19] rRNA is extremely abundant and makes up 80% of the 10 mg/ml RNA found in a typical eukaryotic cytoplasm.[23]

In gene regulation

Several types of RNA can downregulate gene expression by being complementary to a part of a gene. MicroRNAs (miRNA; 21-22 nt) are found in eukaryotes and act through RNA interference (RNAi), where an effector complex of miRNA and enzymes can break down mRNA which the miRNA is complementary to, block the mRNA from being translated, or cause the promoter to be methylated which generally downregulates the gene.[24] Some miRNAs upregulate genes instead (RNA activation).[25] While small interfering RNAs (siRNA; 20-25 nt) are often produced by breakdown of viral RNA, there are also endogenous sources of siRNAs.[26] siRNAs act through RNA interference in a fashion similar to miRNAs, including RNA activation.[27] Animals have Piwi-interacting RNAs (piRNA; 29-30 nt) which are active in germline cells and are thought to be a defense against transposons and play a role in gametogenesis.[28][29] X chromosome inactivation in female mammals is caused by Xist, an RNA which coats one X chromosome, inactivating it.[30] Antisense RNAs are widespread among bacteria; most downregulate a gene, but a few are activators of transcription.[31] An mRNA may contain regulatory elements itself, such as riboswitches, in the 5' UTR or 3' UTR; these cis-regulatory elements regulate the activity of that mRNA.[32]

Image:Uridine to pseudouridine.GIF
Uridine to pseudouridine is a common RNA modification.

In RNA processing

Many RNAs are involved in modifying other RNAs. Introns are spliced out of pre-mRNA by spliceosomes, which contain several small nuclear RNAs (snRNA).[13] RNA can also be altered by having its nucleotides modified to other nucleotides than A, C, G and U. In eukaryotes, modifications of RNA nucleotides are generally directed by small nucleolar RNAs (snoRNA; 60-300 nt),[20] found in the nucleolus and cajal bodies. snoRNAs associate with enzymes and guide them to a spot on an RNA by basepairing to that RNA. These enzymes then perform the nucleotide modification. rRNAs and tRNAs are extensively modified, but snRNAs and mRNAs can also be the target of base modification.[33][34]

List of RNAs

Type Abbr. Function[35] Distribution Ref.
Messenger RNA mRNA Codes for protein All organisms
Ribosomal RNA rRNA Translation All organisms
Transfer RNA tRNA Translation All organisms
Transfer-messenger RNA tmRNA Rescuing stalled ribosomes Bacteria [36]
Antisense RNA aRNA Gene regulation All organisms [37]
Small interfering RNA siRNA Gene regulation Most eukaryotes [38]
MicroRNA miRNA Gene regulation Most eukaryotes [39]
trans-acting siRNA tasiRNA Gene regulation Plants (Arabidopsis thaliana) [40]
Piwi-interacting RNA piRNA Gene regulation Animals [28]
Small nuclear RNA snRNA Various Eukaryotes and archaea [41]
Small nucleolar RNA snoRNA Nucleotide modification of RNAs Eukaryotes and archaea [42]
Guide RNA gRNA mRNA modification Kinetoplastid mitochondria [43]
Ribonuclease P RNase P tRNA maturation All organisms [44]
Ribonuclease MRP RNase MRP rRNA maturation, DNA replication Eukaryotes [45]
Y RNA RNA processing, DNA replication Animals [46]
Telomerase RNA Telomere synthesis Most eukaryotes [47]
Signal recognition particle RNA Protein export All organisms [48]
Retrotransposon Self-propagating Eukaryotes and some bacteria [49]
Viroid Self-propagating Infected plants [50]
Viral genome Information carrier Double-stranded RNA viruses, positive-sense RNA viruses, negative-sense RNA viruses, most satellite viruses and reverse transcribing viruses

Discovery

Nucleic acids were discovered in 1868 by Friedrich Miescher, who called the material 'nuclein' since it was found in the nucleus.[51] It was later discovered that prokaryotic cells, which do not have a nucleus, also contain nucleic acids. The role of RNA in protein synthesis had been suspected since 1939, based on experiments carried out by Torbjörn Caspersson, Jean Brachet and Jack Schultz.[52] Gerard Marbaix isolated the first messenger RNA, for rabbit hemoglobin, and found it induced the synthesis of hemoglobin after injection into oocytes.[53] Severo Ochoa won the 1959 Nobel Prize in Medicine after he discovered how RNA is synthesized.[54] The sequence of the 77 nucleotides of a yeast RNA was found by Robert W. Holley in 1965,[55] winning Holley the 1968 Nobel Prize in Medicine. Carl Woese realised RNA can be catalytic in 1967 and proposed the earliest forms of life relied on RNA both to carry genetic information and to catalyze biochemical reactions—an RNA world.[56][57] In 1976, Walter Fiers and his team at the University of Ghent determined the first complete nucleotide sequence of an RNA virus genome, that of bacteriophage MS2.[58] In the early 1990s it was found that introduced genes can silence homologous endogenous genes in plants.[59] At about the same time, 22 nt long RNAs, now known as microRNAs, were found to have a role in the development of C. elegans.[60] The discovery of gene regulatory RNAs has led to attempts to develop drugs made of RNA, particularly to silence oncogenes and viral genes.[61] There is no such drug on the market, but there is promising research on using siRNAs to downregulate genes through RNA interference.[62]

See also

References

  1. ^ a b
  2. ^ Barciszewski J, Frederic B, Clark C (1999). RNA biochemistry and biotechnology. Springer, 73–87. ISBN 0792358627. 
  3. ^ Salazar M, Fedoroff OY, Miller JM, Ribeiro NS, Reid BR (1992). "The DNA strand in DNAoRNA hybrid duplexes is neither B-form nor A-form in solution". Biochemistry 1993 (32): 4207–15. PMID 7682844.
  4. ^ Hermann T, Patel DJ (2000). "RNA bulges as architectural and recognition motifs". Structure 8 (3): R47–R54. doi:10.1016/S0969-2126(00)00110-6.
  5. ^ Mikkola S, Nurmi K, Yousefi-Salakdeh E, Strömberg R, Lönnberg H (1999). "The mechanism of the metal ion promoted cleavage of RNA phosphodiester bonds involves a general acid catalysis by the metal aquo ion on the departure of the leaving group". Perkin transactions 2: 1619–26. doi:10.1039/a903691a.
  6. ^ Jankowski JAZ, Polak JM (1996). Clinical gene analysis and manipulation: tools, techniques and troubleshooting. Cambridge University Press, 14. ISBN 0521478960. 
  7. ^ Yu Q, Morrow CD (2001). "Identification of critical elements in the tRNA acceptor stem and TΨC loop necessary for human immunodeficiency virus type 1 infectivity". J Virol. 75 (10): 4902–6. doi:10.1128/JVI.75.10.4902-4906.2001.
  8. ^ Elliott MS, Trewyn RW (1983). "Inosine biosynthesis in transfer RNA by an enzymatic insertion of hypoxanthine". J. Biol. Chem. 259 (4): 2407–10. PMID 6365911.
  9. ^ Söll D, RajBhandary U (1995). tRNA: Structure, biosynthesis, and function. ASM Press, 165. ISBN 155581073X. 
  10. ^ Kiss T (2001). "Small nucleolar RNA-guided post-transcriptional modification of cellular RNAs". The EMBO Journal 20: 3617–22. doi:10.1093/emboj/20.14.3617.
  11. ^ King TH, Liu B, McCully RR, Fournier MJ (2002). "Ribosome structure and activity are altered in cells lacking snoRNPs that form pseudouridines in the peptidyl transferase center". Molecular Cell 11 (2): 425–35. doi:10.1016/S1097-2765(03)00040-6.
  12. ^ Mathews DH, Disney MD, Childs JL, Schroeder SJ, Zuker M, Turner DH (2004). "Incorporating chemical modification constraints into a dynamic programming algorithm for prediction of RNA secondary structure". Proc. Natl. Acad. Sci. USA 101 (19): 7287–92. doi:10.1073/pnas.0401799101.
  13. ^ a b c
  14. ^ Higgs PG (2000). "RNA secondary structure: physical and computational aspects". Quarterly Reviews of Biophysics 33: 199–253. doi:10.1017/S0033583500003620.
  15. ^ a b Nissen P, Hansen J, Ban N, Moore PB, Steitz TA (2000). "The structural basis of ribosome activity in peptide bond synthesis". Science 289 (5481): 920–30. doi:10.1126/science.289.5481.920.
  16. ^ Nudler E, Gottesman ME (2002). "Transcription termination and anti-termination in E. coli". Genes to Cells 7: 755–68. doi:10.1046/j.1365-2443.2002.00563.x.
  17. ^ Jeffrey L Hansen, Alexander M Long, Steve C Schultz (1997). "Structure of the RNA-dependent RNA polymerase of poliovirus". Structure 5 (8): 1109-22. doi:10.1016/S0969-2126(97)00261-X.
  18. ^ Ahlquist P (2002). "RNA-Dependent RNA Polymerases, Viruses, and RNA Silencing". Science 296 (5571): 1270–73. doi:10.1126/science.1069132.
  19. ^ a b c
  20. ^ a b c
  21. ^ Rossi JJ (2004). "Ribozyme diagnostics comes of age". Chemistry & Biology 11 (7): 894–95. doi:10.1016/j.chembiol.2004.07.002.
  22. ^ Blevins T et al (2006). "Four plant Dicers mediate viral small RNA biogenesis and DNA virus induced silencing". Nucleic Acids Res 34 (21): 6233–46. PMID 17090584.
  23. ^ Kampers T, Friedhoff P, Biernat J, Mandelkow E-M, Mandelkow E (1996). "RNA stimulates aggregation of microtubule-associated protein tau into Alzheimer-like paired helical filaments". FEBS Letters 399: 98–100, 344–49. PMID 8985176.
  24. ^ Matzke MA, Matzke AJM (2004). "Planting the seeds of a new paradigm". PLoS Biology 2 (5): e133. doi:10.1371/journal.pbio.0020133.
  25. ^ Check E (2007). "RNA interference: hitting the on switch". Nature 448 (7156): 855–58. doi:10.1038/448855a.
  26. ^ Vazquez F, Vaucheret H, Rajagopalan R, Lepers C, Gasciolli V, Mallory AC, Hilbert J, Bartel DP, Crété P (2004). "Endogenous trans-acting siRNAs regulate the accumulation of Arabidopsis mRNAs". Molecular Cell 16 (1): 69–79. doi:10.1016/j.molcel.2004.09.028.
  27. ^ Doran G (2007). "RNAi – Is one suffix sufficient?". Journal of RNAi and Gene Silencing 3 (1): 217–19.
  28. ^ a b Horwich MD, Li C Matranga C, Vagin V, Farley G, Wang P, Zamore PD (2007). "The Drosophila RNA methyltransferase, DmHen1, modifies germline piRNAs and single-stranded siRNAs in RISC". Current Biology 17: 1265–72. doi:10.1016/j.cub.2007.06.030.
  29. ^ Girard A, Sachidanandam R, Hannon GJ, Carmell MA (2006). "A germline-specific class of small RNAs binds mammalian Piwi proteins". Nature 442: 199–202. doi:10.1038/nature04917.
  30. ^ Heard E, Mongelard F, Arnaud D, Chureau C, Vourc'h C, Avner P (1999). "Human XIST yeast artificial chromosome transgenes show partial X inactivation center function in mouse embryonic stem cells". Proc. Natl. Acad. Sci. USA 96 (12): 6841–46. PMID 10359800.
  31. ^ Wagner EG, Altuvia S, Romby P (2002). "Antisense RNAs in bacteria and their genetic elements". Adv Genet. 46: 361–98. PMID 11931231.
  32. ^ Batey RT (2006). "Structures of regulatory elements in mRNAs". Curr. Opin. Struct. Biol. 16 (3): 299–306. doi:10.1016/j.sbi.2006.05.001. PMID 16707260.
  33. ^ Covello PS, Gray MW (1989). "RNA editing in plant mitochondria". Nature 341: 662–66. doi:10.1038/341662a0.
  34. ^ Omer AD, Ziesche S, Decatur WA, Fournier MJ, Dennis PP (2003). "RNA-modifying machines in archaea". Molecular Microbiology 48 (3): 617–29. doi:10.1046/j.1365-2958.2003.03483.x.
  35. ^ Unless else specified in boxes, then listing of housekeeping RNAs follows: Szymanski J, Barciszewska MZ, Zywicki M, Barciszewski J (2003). "Noncoding RNA transcripts". J. Appl. Genet. 44 (1): 9. PMID 12590177.
  36. ^ Gillet R, Felden B (2001). "Emerging views on tmRNA-mediated protein tagging and ribosome rescue". Molecular Microbiology 42 (4): 879–85. doi:10.1046/j.1365-2958.2001.02701.x.
  37. ^ Brantl S (2002). "Antisense-RNA regulation and RNA interference". Biochimica et Biophysica Acta 1575 (1–3): 15–25. PMID 12020814.
  38. ^ Ahmad K, Henikoff S (2002). "Epigenetic consequences of nucleosome dynamics". Cell 111 (3): 281–84. doi:10.1016/S0092-8674(02)01081-4.
  39. ^ Lin S-L, Miller JD, Ying S-Y (2006). "Intronic microRNA (miRNA)". Journal of Biomedicine and Biotechnology: 1–13. PMID 17057362.
  40. ^ Vazquez F, Vaucheret H (2004). "Endogenous trans-acting siRNAs regulate the accumulation of Arabidopsis mRNAs". Mol. Cell (16): 1–13. PMID 17057362.
  41. ^ Thore S, Mayer C, Sauter C, Weeks S, Suck D (2003). "Crystal Structures of the Pyrococcus abyssi Sm Core and Its Complex with RNA". J. Biol. Chem. 278 (2): 1239–47. doi:10.1074/jbc.M207685200.
  42. ^ Kiss T (2001). "Small nucleolar RNA-guided post-transcriptional modification of cellular RNAs". The EMBO Journal 20: 3617–22. doi:10.1093/emboj/20.14.3617.
  43. ^ Alfonzo JD, Thiemann O, Simpson L (1997). "The mechanism of U insertion/deletion RNA editing in kinetoplastid mitochondria". Nucleic Acids Research 25 (19): 3751–59. PMID 9380494.
  44. ^ Pannucci JA, Haas ES, Hall TA, Harris JK, Brown JW (1999). "RNase P RNAs from some Archaea are catalytically active". Proc Natl Acad Sci USA 96 (14): 7803–08. PMID 10393902.
  45. ^ Woodhams MD, Stadler PF, Penny D, Collins LJ (2007). "RNase MRP and the RNA processing cascade in the eukaryotic ancestor". BMC Evolutionary Biology 7: S13. doi:10.1186/1471-2148-7-S1-S13.
  46. ^ Perreault J, Perreault J-P, Boire G (2007). "Ro-associated Y RNAs in metazoans: evolution and diversification". Molecular Biology and Evolution 24 (8): 1678–89. doi:10.1093/molbev/msm084.
  47. ^ Lustig AJ (1999). "Crisis intervention: The role of telomerase". Proc Natl Acad Sci USA 96 (7): 3339–41. PMID 10097039.
  48. ^ Gribaldo1 S, Brochier-Armanet C (2006). "The origin and evolution of Archaea: a state of the art". Philos Trans R Soc Lond B Biol Sci. 361 (1470): 1007–22. PMID 16754611.
  49. ^ Boeke JD (2003). "The unusual phylogenetic distribution of retrotransposons: a hypothesis". Genome Research 13: 1975–83. PMID 12952870.
  50. ^ Flores R, Hernández C, Martínez de Alba AE, Daròs JA, Di Serio F (2005). "Viroids and viroid-host interactions". Annual Review of Phytopathology 43: 117–39. PMID 16078879.
  51. ^ Dahm R (2005). "Friedrich Miescher and the discovery of DNA". Developmental Biology 278 (2): 274–88. PMID 15680349.
  52. ^ Nierhaus KH, Wilson DN (2004). Protein Synthesis and Ribosome Structure. Wiley-VCH, 3. ISBN 3527306382. 
  53. ^ Carlier M (June 2003). L'ADN, cette "simple" molécule. Esprit libre.
  54. ^ Ochoa S (1959). Enzymatic synthesis of ribonucleic acid. Nobel Lecture.
  55. ^ Holley RW et al (1965). "Structure of a ribonucleic acid". Science 147 (1664): 1462–65. doi:10.1126/science.147.3664.1462.
  56. ^ Siebert S (2006). Common sequence structure properties and stable regions in RNA secondary structures. Dissertation, Albert-Ludwigs-Universität, Freiburg im Breisgau 1.
  57. ^ Szathmáry E (1999). "The origin of the genetic code: amino acids as cofactors in an RNA world". Trends Genet. 15 (6): 223–9. doi:10.1016/S0168-9525(99)01730-8.
  58. ^ Fiers W et al (1976). "Complete nucleotide-sequence of bacteriophage MS2-RNA: primary and secondary structure of replicase gene". Nature 260: 500–7. PMID 1264203.
  59. ^ Napoli C, Lemieux C, Jorgensen R (1990). "Introduction of a chimeric chalcone synthase gene into petunia results in reversible co-suppression of homologous genes in trans.". Plant Cell 2 (4): 279–89. PMID 12354959.
  60. ^ Ruvkun G (2001). "Glimpses of a tiny RNA world". Science 294 (5543): 797–99. doi:10.1126/science.1066315.
  61. ^ Trent RJ (2005). Molecular Medicine, 3rd edition, Elsevier, 160–63. ISBN 0-12-699057-3. 
  62. ^ Fichou Y, Férec C (2006). "The potential of oligonucleotides for therapeutic applications". Trends in Biotechnology 24 (12): 563–70. doi:10.1016/j.tibtech.2006.10.003.


External links


v  d  e
Major families of biochemicals
Peptides | Amino acids | Nucleic acids | Carbohydrates | Nucleotide sugars | Lipids | Terpenes | Carotenoids | Tetrapyrroles | Enzyme cofactors | Steroids | Flavonoids | Alkaloids | Polyketides | Glycosides
Analogues of nucleic acids: Types of nucleic acids Analogues of nucleic acids:
Nucleobases: Purine (Adenine, Guanine) | Pyrimidine (Uracil, Thymine, Cytosine)
Nucleosides: Adenosine/Deoxyadenosine | Guanosine/Deoxyguanosine | Uridine | Thymidine | Cytidine/Deoxycytidine
Nucleotides: monophosphates (AMP, GMP, UMP, CMP) | diphosphates (ADP, GDP, UDP, CDP) | triphosphates (ATP, GTP, UTP, CTP) | cyclic (cAMP, cGMP, cADPR)
Deoxynucleotides: monophosphates (dAMP, dGMP, TMP, dCMP) | diphosphates (dADP, dGDP, TDP, dCDP) | triphosphates (dATP, dGTP, TTP, dCTP)
Ribonucleic acids: RNA | mRNA (pre-mRNA/hnRNA) | tRNA | rRNA | aRNA | gRNA | miRNA | ncRNA | piRNA | shRNA | siRNA | snRNA | snoRNA | tmRNA
Deoxyribonucleic acids: DNA | cDNA | gDNA | msDNA | mtDNA
Nucleic acid analogues: GNA | LNA | PNA | TNA | morpholino
Cloning vectors: phagemid | plasmid | lambda phage | cosmid | P1 phage | fosmid | BAC | YAC | HAC

ar:حمض ريبي نووي

bn:আরএনএ zh-min-nan:RNA bs:Ribonukleinska kiselina br:Trenkenn ribonukleek bg:РНК ca:Àcid ribonucleic cs:RNA da:RNA de:Ribonukleinsäure et:Ribonukleiinhape el:RNA es:Ácido ribonucleico eo:RNA eu:Azido erribonukleiko fo:RNA fr:Acide ribonucléique gl:Ácido ribonucleico ko:RNA hr:Ribonukleinska kiselina id:Asam ribonukleat is:RKS it:RNA he:RNA la:Acidum ribonucleicum lv:Ribonukleīnskābe lb:RNS lt:Ribonukleino rūgštis hu:RNS mk:РНК mn:РНХ nl:RNA ja:リボ核酸 ka:რიბონუკლეინის მჟავა no:RNA nn:Ribonukleinsyre oc:Acid ribonucleïc pl:Kwasy rybonukleinowe pt:RNA ro:ARN ru:Рибонуклеиновые кислоты simple:RNA sk:Ribonukleová kyselina sl:Ribonukleinska kislina sr:Рибонуклеинска киселина sh:Ribonukleinska kiselina fi:RNA sv:Ribonukleinsyra ta:ரைபோ கரு அமிலம் te:రైబో కేంద్రక ఆమ్లం th:อาร์เอ็นเอ vi:RNA tr:RNA uk:РНК ur:رائبو مرکزی ترشہ yo:RNA

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