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RNA

Ribonucleic acid is a polymeric molecule essential in various biological roles in coding, decoding and expression of genes. RNA and DNA are nucleic acids, along with lipids and carbohydrates, constitute the four major macromolecules essential for all known forms of life. Like DNA, RNA is assembled as a chain of nucleotides, but unlike DNA, RNA is found in nature as a single strand folded onto itself, rather than a paired double strand. Cellular organisms use messenger RNA to convey genetic information that directs synthesis of specific proteins. Many viruses encode their genetic information using an RNA genome; some RNA molecules play an active role within cells by catalyzing biological reactions, controlling gene expression, or sensing and communicating responses to cellular signals. One of these active processes is protein synthesis, a universal function in which RNA molecules direct the synthesis of proteins on ribosomes; this process uses transfer RNA molecules to deliver amino acids to the ribosome, where ribosomal RNA links amino acids together to form coded proteins.

Like DNA, most biologically active RNAs, including mRNA, tRNA, rRNA, snRNAs, other non-coding RNAs, contain self-complementary sequences that allow parts of the RNA to fold and pair with itself to form double helices. Analysis of these RNAs has revealed that they are structured. Unlike DNA, their structures do not consist of long double helices, but rather collections of short helices packed together into structures akin to proteins. In this fashion, RNAs can achieve chemical catalysis. For instance, determination of the structure of the ribosome—an RNA-protein complex that catalyzes peptide bond formation—revealed that its active site is composed of RNA; each nucleotide in RNA contains a ribose sugar, with carbons numbered 1' through 5'. A base is attached to the 1' position, in general, cytosine, guanine, or uracil. Adenine and guanine are purines and uracil are pyrimidines. A phosphate group is attached to the 5' position of the next; the phosphate groups have a negative charge each. The bases form hydrogen bonds between cytosine and guanine, between adenine and uracil and between guanine and uracil.

However, other interactions are possible, such as a group of adenine bases binding to each other in a bulge, or the GNRA tetraloop that has a guanine–adenine base-pair. An important structural component 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 causes the helix to take the A-form geometry, although in single strand dinucleotide contexts, RNA can also adopt the B-form most observed in DNA. The A-form geometry results in a deep and narrow major groove and a shallow and wide minor groove. A second consequence of the presence of the 2'-hydroxyl group is that in conformationally flexible regions of an RNA molecule, it can chemically attack the adjacent phosphodiester bond to cleave the backbone. RNA is transcribed with only four bases, but these bases and attached sugars can be modified in numerous ways as the RNAs mature. Pseudouridine, in which the linkage between uracil and ribose is changed from a C–N bond to a C–C bond, ribothymidine are found in various places.

Another notable modified base is hypoxanthine, a deaminated adenine base whose nucleoside is called inosine. Inosine plays a key role in the wobble hypothesis of the genetic code. There are more than 100 other occurring modified nucleosides; the greatest structural diversity of modifications can be found in tRNA, while pseudouridine and nucleosides with 2'-O-methylribose present in rRNA are the most common. The specific roles of many of these modifications in RNA are not understood. However, it is notable that, in ribosomal RNA, many of the post-transcriptional modifications occur in functional regions, such as the peptidyl transferase center and the subunit interface, implying that they are important for normal function; the functional form of single-stranded RNA molecules, just like proteins requires a specific tertiary structure. The scaffold for this structure is provided by secondary structural elements that are hydrogen bonds within the molecule; this leads to several recognizable "domains" of secondary structure like hairpin loops and internal loops.

Since RNA is charged, metal ions such as Mg2+ are needed to stabilise many secondary and tertiary structures. The occurring enantiomer of RNA is D-RNA composed of D-ribonucleotides. All chirality centers are located in the D-ribose. By the use of L-ribose or rather L-ribonucleotides, L-RNA can be synthesized. L-RNA is much more stable against degradation by RNase. Like other structured biopolymers such as proteins, one can define topology of a folded RNA molecule; this is done based on arrangement of intra-chain contacts within a folded RNA, termed as circuit topology. Synthesis of RNA is catalyzed by an enzyme—RNA polymerase—using DNA as a template, a process known as transcription. Initiation of transcription begins with the binding of the enzyme to a promoter sequence in the DNA; the DNA double helix is unwound by the helicase activity of the enzyme. The enzyme progresses along the template strand in the 3’ to 5’ direction, synthesizing a complementary RNA molecule with elongation occur

Warcraft: Day of the Dragon

Warcraft: Day of the Dragon is a novel by Richard A. Knaak based in Blizzard Entertainments Warcraft Universe, it was published by Pocket Books. It is the second book released in the Warcraft Universe, the first released paper book. Set after Warcraft II: Tides of Darkness but before Warcraft III: Reign of Chaos, Day of the Dragon is the story of how a human Mage, ventures into the last remaining Orc-controlled lands in Khaz Modan by the order of Krasus. Krasus is a red dragon named Korialstrasz, yet is disguised as a human mage of Dalaran during the earlier chapters of the book, he is loyal to his captured queen, Queen of the Red dragon flight and one of the five great Aspects. By using the "Demon Soul", Nekros Skullcrusher, leader of the orcs in Khaz Modan, is able to hold Alexstrasza and her consorts, such as Tyranastrasz, against their will and use their offspring as pawns against the other races of Azeroth. Whilst Korialstrasz sought help from the other Aspects, Nozdormu and Ysera, Deathwing helped Rhonin get into the Orc Fortress in order to convince Nekros Skullcrusher that there was an imminent Alliance attack on Grim Batol.

Deathwing's real motivation was that he wanted the eggs so he could replenish his flight, not to free the Red Dragonqueen. Believing a great army to be on its way, Nekros had the eggs transported elsewhere, placing them in the open where Deathwing wanted them. However, as Deathwing was stealing the eggs, he was confronted by a dying Tyranastrasz. Despite initial problems, Korialstrasz managed to gain the aid of the other three Great Aspects in his task to free Alexstrasza. With the help of Rhonin, Vereesa Windrunner, Falstad Dragonreaver, a number of dwarven resistance fighters, the group managed to destroy the "Demon Soul" forever. By doing so, they free Alexstrasza, who swallows Nekros Skullcrusher in one gulp, aiding in the defeat of the orcs in the area. Deathwing helped with the release of Alexstrasza, yet was not concerned due to the fact that the "Demon Soul" has drained the other Aspects powers. However, with the destruction of the "Demon Soul" the powers were returned to the four Aspects and Deathwing was last seen fleeing from three angry Aspects at the time as Alexstrasza went to Korialstrasz.

The storyline covers Deathwing's plot to throw the mortal kingdoms into disarray by posing as Lord Prestor, using his draconic powers to manipulate the rulers of the human kingdoms into making him king of Alterac planning to marry into the Lordaeron royal family to become its heir. However, with his defeat at the hands of the other four Dragon Aspects, Lord Prestor is never seen again. Neltharion / Deathwing the Destroyer and Dragon Aspect of Death, Primary antagonist of the novel, a dragon aspect. Korialstrasz, Alextrasza's third mate and King of the Red Dragonflight. Alexstrasza, Dragon Aspect of Life, captured by the orcs. Dragon Aspects of Dreams Nature Magic and Time: Ysera, Malygos. Tyranastrasz, Alextrasza's first mate and King of the Red Dragonflight. Rhonin, A human wizard of the Kirin Tor. Vereesa Windrunner, Sister to Alleria and Sylvanas Windrunner, Elven ranger. Falstad, Dwarven warrior. Nekros Skullcrusher, An orcish warlock, wielder of the Demon Soul. Kryll, A goblin working both for Neltharion and Nekros.

Medivh. Duncan Senturus, A member of the Knights of the Silver Hand. King Terenas Menethil, King of Lordaeron. Torgus, An orcish Dragon rider. Little of the content covered in Day of the Dragon is within the game World of Warcraft; the location of Grim Batol has been in the game since its release in 2004, with the release of World of Warcraft: Cataclysm, it serves as a five player dungeon. The remains of the Dragonmaw Orc clan are still present in the area, known as the Wetlands, a large number of red dragonspawn are present, guarding Grim Batol, hostile to all others; the storyline of the Prestor family attempting to throw the Alliance into disarray continued, as Deathwing's daughter took place as part of the noble family, became a royal advisor to the kingdom of Stormwind before being discovered to be, in fact, the dragon Onyxia. Onyxia has since been slain; the Red Dragonflight have recovered since their imprisonment in Day of the Dragon, in World of Warcraft are a strong presence in the Wyrmrest Accord, an alliance between dragons.

Korialstraz sits beside Alexstrasza in the accords's base of the Wyrmrest Temple. Rhonin and Veressa Windrunner are found in game, leaders of the kingdom of Dalaran in Northrend. List of novels based on video games Day of the Dragon on Wowpedia, a Warcraft wiki

Westrail

Westrail was the trading name of the Western Australian Government Railways from September 1975 until December 2000, when the WAGR's freight division and the Westrail name and logo were privatised. The WAGR had its origins in 1879, when the Department of Railways was established. In 1890, the Department was abolished and replaced by the WAGR and the Department of Works & Buildings. In September 1975, the WAGR adopted an associated logo. However, the official name of the WAGR was not changed; the new name was the main element of a complete program to improve the WAGR's public image. Every visible feature of the organisation was to be associated with the new Westrail identity; the transition from WAGR to Westrail began, with the new name and universally replacing the old one in the vocabulary of staff and the public. Strong impetus to acceptance of the new corporate identity was given by the completion of a new Westrail office headquarters and passenger facility at East Perth Terminal; the new building, named the Westrail Centre, was opened by the Premier of Western Australia, Sir Charles Court, on 12 November 1976.

Westrail was responsible for managing the state's rail infrastructure. It operated regional passenger and freight services throughout Western Australia. In Perth, Westrail provided the metropolitan area rail service, under contract to another arm of the State government, its country passenger services involved the operation of both trains and road coaches. In October 1987, it was announced by Premier Brian Burke and Federal Minister for Land Transport & Infrastructure Support, Peter Duncan, that a merger of Westrail with Australian National was being investigated. Nothing came of it. On 17 December 2000, the WAGR's freight division along with the Westrail name and logo were sold to Australia Western Railroad, a subsidiary of the Australian Railroad Group; the deal saw the WAGR's freight lines leased to ARG for 99 years. The WAGR's remaining functions, including owning the rail network and operating regional passenger services, were transferred to the Western Australian Government Railways Commission.

On 1 January 2003, the WAGR Commission's functions were absorbed by the Public Transport Authority. The former Westrail Centre is now known as the Public Transport Centre. Westrail applied an orange with blue stripe livery to its locomotives and passenger vehicles. Freight rolling stock and road trucks were painted yellow, blue was used on all signs and printed material; the Westrail logo incorporated a stylised "W" surmounted by a solid bar representing a railway track. Between the bar and the "W" was the word "Westrail". In July 1997, a yellow with blue livery was unveiled when the first Q class diesel-electric locomotive was delivered. From 1975 until 1981, Westrail News Letter was published as a staff newsletter. Rail transport in Western Australia Transperth Transwa