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By convention, the coding strand is the strand used when displaying a DNA sequence. It is presented in the 5' to 3' direction. Wherever a gene exists on a DNA molecule, one strand is the coding strand (or sense strand), and the other is the noncoding strand (also called the antisense strand, [3] anticoding strand, template strand or transcribed ...
DNA polymerases in general cannot initiate synthesis of new strands but can only extend an existing DNA or RNA strand paired with a template strand. To begin synthesis, a short fragment of RNA, called a primer, must be created and paired with the template DNA strand.
In DNA replication, DNA-dependent DNA polymerases make copies of DNA polynucleotide chains. To preserve biological information, it is essential that the sequence of bases in each copy are precisely complementary to the sequence of bases in the template strand.
DNA replication also works by using a DNA template, the DNA double helix unwinds during replication, exposing unpaired bases for new nucleotides to hydrogen bond to. Gene synthesis, however, does not require a DNA template and genes are assembled de novo. DNA synthesis occurs in all eukaryotes and prokaryotes, as well as some viruses. The ...
The non-template (sense) strand of DNA is called the coding strand, because its sequence is the same as the newly created RNA transcript (except for the substitution of uracil for thymine). This is the strand that is used by convention when presenting a DNA sequence.
The two DNA strands then become templates for DNA polymerase to enzymatically assemble a new DNA strand from free nucleotides, the building blocks of DNA. As PCR progresses, the DNA generated is itself used as a template for replication, setting in motion a chain reaction in which the original DNA template is exponentially amplified.
DNA is transcribed into mRNA molecules, which travel to the ribosome where the mRNA is used as a template for the construction of the protein strand. Since nucleic acids can bind to molecules with complementary sequences, there is a distinction between " sense " sequences which code for proteins, and the complementary "antisense" sequence ...
Any given sequence of DNA can therefore be read in six different ways: Three reading frames in one direction (starting at different nucleotides) and three in the opposite direction. During transcription, the RNA polymerase read the template DNA strand in the 3′→5′ direction, but the mRNA is formed in the 5′ to 3′ direction. [3]