A Brief Explanation of an Over-the-Counter Market | Definition. A over-the-counter market (OTC) refers to a decentralized and informal way of exchanging stocks, derivatives, or other assets between two parties.
The leading strand is built by using the lagging strand of the old molecule as the template. Replication of the leading strand begins with the enzyme âprimaseâ. Primase adds a small complementary piece of RNA (~10 nucleotides), called an âRNA primerâ, near the end of the lagging strand. The RNA primer gives an enzyme called âDNA polymerase IIIâ something to attach a DNA nucleotide to. A jury-rigged design, RNA primers are necessary because DNA polymerase III can only attach nucleotides to the 3â end of a pre-existing nucleotide.
Once RNA polymerase and its related transcription factors are in place, the single-stranded DNA is exposed and ready for transcription. At this point, RNA polymerase begins moving down the DNA template strand in the 3' to 5' direction, and as it does so, it strings together complementary nucleotides. By virtue of complementary base- pairing, this action creates a new strand of mRNA that is organized in the 5' to 3' direction.