Protein Synthesis(406-407)
Overview of Protein Synthesis
And RNA Processing
DNA
Making Proteins
This image summarizes
the processes of
transcription and
translation.
mRNA
rRNA
What are the three
stages in this process
(central dogma) and
where are they in this
picture?
protein
tRNA
RNA
• RNA (Ribonucleic Acid)
– Contains Ribose as the sugar in its sugarphosphate backbone
• RNA has Uracil rather than Thymine as a base
– Base pairs: A – U C – G
• 3 types of RNA
– messenger (mRNA)
– transfer (tRNA)
– ribosomal (rRNA)
Two Steps to Protein Synthesis
1. Transcription: mRNA is made from a strand of
DNA
2. Translation: Protein is made by a ribosome by
using mRNA as the set of “instructions.”
Two Steps to Protein Synthesis
1. Transcription: mRNA is made from a strand of
DNA
2. Translation: Protein is made by a ribosome by
using mRNA as the set of “instructions.”
Transcription
in Prokaryotes
• DNA is transcribed into
mRNA
Translation
in Prokaryotes
• mRNA serves as the
instructional material to
make proteins
Transcription
in Eukaryotes
• DNA is transcribed into
pre-mRNA
RNA Processing
in Eukaryotes
• Non-coding regions of
the mRNA, called
introns, are removed
from the pre-mRNA.
Translation
in Eukaryotes
• The mRNA with only the
coding region (the
exons) leaves the
nucleus.
• Translation from mRNA
to protein occurs in the
cytoplasm.