Question

How to make RNA from a DNA ?

Answer 1

The process by which RNA is made from a DNA is called as Transcription.Transcription is the first step of gene expression, in which a particular segment of DNA is copied into RNA by the enzyme RNA polymerase.

Answer 2

The entire process can be reduced to following steps.
1)One or more sigma factors initiate transcription of a gene by enabling binding of RNA polymerase to promoter DNA.
2)RNA polymerase moves a transcription bubble, like the slider of a zipper, which splits the double helix DNA molecule into two strands of unpaired DNA nucleotides, by breaking the hydrogen bonds between complementary DNA nucleotides.
3)RNA polymerase adds matching RNA nucleotides that are paired with complementary DNA nucleotides of one DNA strand.
4)RNA sugar-phosphate backbone forms with assistance from RNA polymerase to form an RNA strand.
5)Hydrogen bonds of the untwisted RNA + DNA helix break, freeing the newly synthesized RNA strand.
6)If the cell has a nucleus, the RNA may be further processed (with the addition of a 3'UTR poly-A tail and a 5'UTR cap) and exits to the cytoplasm through the nuclear pore complex.