RNA transcription

Bio Synthesis of proteins

• Transcription

• Translation

Transcription is the process of copying out the DNA sequence of a gene in the similar alphabet of RNA. The synthesis of RNA using DNA as a template.

The goal of transcription is to make a RNA copy of a gene's DNA sequence

RNA polymerase has multiple roles in transcription

• Uses a single-stranded DNA template to synthesize a complementary strand of RNA

• Unwinds DNA double helix and separates it into two strands

• Positions RNA nucleotides on the template strand

• links RNA nucleotides by covalent sugar-phosphate bonds

• Detaches assembled RNA allowing DNA helix to reform

mRNA

Messenger RNA

When DNA is translated it is unwind-ed into two strands, what are they called?

Sense and anti-sense strand

Instead of thymine, what nucleotide does RNA have?

Uracil

• mRNA is complimentary to anti-sense strand, but is identical to sense strand

• The sense strand of DNA contains the information about proteins

• Transcription occurs from 5’ to 3’

Example:

Sense Strand : AGGTACCTTGC

Anti-Sense: TCCATGGAACG

mRNA: AGGUACCUUGC

If the sense strand has : TTATACCATGAC, find anti-sense strand and RNA transcribed strand.

Anti-sense strand: AATATGGTACAG

mRNA: UUAUACCUACUG