Transcription (DNA to RNA)
The human genome contains around 30,000 genes, each
of which codes for specific proteins. Although large
sections of DNA in the human genome are transcribed,
they do not code for proteins. The process of
transcription occurs in two main steps: The enzyme RNA
polymerase forms a pre-messenger RNA molecule by
using base pairs that are complementary to the base
sequence of the DNA template strand. This step takes
place in the nucleus. The pre-mRNA is edited by more
enzymes to produce a desired mRNA, which is the final
product of transcription. RNA polymerase uses
nucleotides according to the base pair rules to create an
RNA copy. In previous videos, we learned how DNA is
copied by DNA polymerase to form an identical new
strand of DNA. The next step in the transcription process
is to copy the bases on the DNA template strand to form
a new complementary RNA strand. Essentially, these
two processes represent how the pre-mRNA is
processed. The first step involves adding a cap and a
tail to the ends of the pre-messenger RNA molecule. The
second step involves removing any non-coding parts,
also known as introns, that do not code for proteins.
This process is known as RNA splicing, in which the
protein-RNA complex known as the spliceosome
removes these introns.
The human genome contains around 30,000 genes, each
of which codes for specific proteins. Although large
sections of DNA in the human genome are transcribed,
they do not code for proteins. The process of
transcription occurs in two main steps: The enzyme RNA
polymerase forms a pre-messenger RNA molecule by
using base pairs that are complementary to the base
sequence of the DNA template strand. This step takes
place in the nucleus. The pre-mRNA is edited by more
enzymes to produce a desired mRNA, which is the final
product of transcription. RNA polymerase uses
nucleotides according to the base pair rules to create an
RNA copy. In previous videos, we learned how DNA is
copied by DNA polymerase to form an identical new
strand of DNA. The next step in the transcription process
is to copy the bases on the DNA template strand to form
a new complementary RNA strand. Essentially, these
two processes represent how the pre-mRNA is
processed. The first step involves adding a cap and a
tail to the ends of the pre-messenger RNA molecule. The
second step involves removing any non-coding parts,
also known as introns, that do not code for proteins.
This process is known as RNA splicing, in which the
protein-RNA complex known as the spliceosome
removes these introns.
