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DNA stands for deoxyribonucleic acid while RNA stands for ribonucleic acid. RNA is very similar to DNA but differs in a few important structural details RNA is usually single stranded while DNA is usually double stranded in biotechnology world. RNA nucleotides contain ribose while DNA contains deoxyribose a type of ribose that lacks one oxygen atom and RNA uses the nucleotide uracil in its composition instead of 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 them guided by noncoding RNAs.
DNA stands for deoxyribonucleic acid while RNA stands for ribonucleic acid. RNA is very similar to DNA but differs in a few important structural details RNA is usually single stranded while DNA is usually double stranded in biotechnology world. RNA nucleotides contain ribose while DNA contains deoxyribose a type of ribose that lacks one oxygen atom and RNA uses the nucleotide uracil in its composition instead of 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 them guided by noncoding RNAs.
DNA sequencing reactions are just like the PCR reactions for replicating DNA. the template DNA, free nucleotides, an enzyme a 'primer' - a small piece of single-stranded DNA about 20-30 nt long that can hybridize to one strand of the template DNA.
In DNA however uracil is readily produced by chemical degradation of cytosine so having thymine as the normal base makes detection and repair of such incipient mutations more efficient. Thus uracil is appropriate for RNA where quantity is important but lifespan is not whereas thymine is appropriate for DNA where maintaining sequence with high fidelity is more critical.There are also numerous modified bases and sugars found in RNA that serve many different roles. Pseudouridine in which the linkage between uracil and ribose is changed from a C–N bond to a bond and ribothymidine T are found in various places most notably in the loop of tRNA. Another notable modified base is hypoxanthine a deaminated guanine base whose nucleoside is called inosine.
Most important structural feature of RNA that distinguishes it from DNA is the presence of a hydroxyl group at the position of the ribose sugar. The presence of this functional group enforces the Cendo sugar conformation as opposed to the Cendo conformation of the deoxyribose sugar in DNA that causes the helix to adopt the A form geometry rather than the Bform most commonly observed in DNA.
In DNA however uracil is readily produced by chemical degradation of cytosine so having thymine as the normal base makes detection and repair of such incipient mutations more efficient. Thus uracil is appropriate for RNA where quantity is important but lifespan is not whereas thymine is appropriate for DNA where maintaining sequence with high fidelity is more critical.There are also numerous modified bases and sugars found in RNA that serve many different roles. Pseudouridine in which the linkage between uracil and ribose is changed from a C–N bond to a bond and ribothymidine T are found in various places most notably in the loop of tRNA. Another notable modified base is hypoxanthine a deaminated guanine base whose nucleoside is called inosine.
Most important structural feature of RNA that distinguishes it from DNA is the presence of a hydroxyl group at the position of the ribose sugar. The presence of this functional group enforces the Cendo sugar conformation as opposed to the Cendo conformation of the deoxyribose sugar in DNA that causes the helix to adopt the A form geometry rather than the Bform most commonly observed in DNA.
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