protein synthesis model
TRANSCRIPT
Protein SynthesisBy Steven Detrie
Nucleus
Ribosomes
Cytoplasm
---------------------TACTCTGGCATCACT-------------------------------------------------ATGAGACCGTAGTGA---------------------------
Hydrogen Bonds
Coding Region
Start codon
Stop codon
---------------------TACTCTGGCATCACT-------------------------------------------------ATGAGACCGTAGTGA---------------------------
This is RNA polymerase.
---------------------TACTCTGGCATCACT-------------------------------------------------ATGAGACCGTAGTGA---------------------------
This is RNA polymerase.
---------------------TACTCTGGCATCACT-------------------------------------------------ATGAGACCGTAGTGA---------------------------
This is RNA polymerase.
ACG
---------------------TACTCTGGCATCACT-------------------------------------------------ATGAGACCGTAGTGA---------------------------
Hydrogen Bonds
This is RNA polymerase.
ACG AGA
---------------------TACTCTGGCATCACT-------------------------------------------------ATGAGACCGTAGTGA---------------------------
This is RNA polymerase.
ACG AGA CCG
---------------------TACTCTGGCATCACT-------------------------------------------------ATGAGACCGTAGTGA---------------------------
This is RNA polymerase.
ACG AGA CCG UAG
---------------------TACTCTGGCATCACT-------------------------------------------------ATGAGACCGTAGTGA---------------------------
This is RNA polymerase.
ACG AGA CCG UAG UGA
---------------------TACTCTGGCATCACT-------------------------------------------------ATGAGACCGTAGTGA---------------------------
This is RNA polymerase.
ACG AGA CCG UAG UGA
MRNA strand
---------------------TACTCTGGCATCACT-------------------------------------------------ATGAGACCGTAGTGA---------------------------
This is RNA polymerase.
ACG AGA CCG UAG UGA
---------------------TACTCTGGCATCACT-------------------------------------------------ATGAGACCGTAGTGA---------------------------
This is RNA polymerase.
ACG AGA CCG UAG UGA
Nucleus
Ribosomes
ACG AGA CCG UAG UGA
Nuclear Pore
Nucleus
Ribosomes
ACG AGA CCG UAG UGA
Nucleus
Ribosomes
ACG AGA CCG UAG UGA
ACG AGA CCG UAG UGA
AC
G A
GA
CC
G U
AG
UG
A
AC
G A
GA
CC
G U
AG
UG
A
ACG AGA CCG UAG UGA
ACG AGA CCG UAG UGA
ACG AGA CCG UAG UGA
ACG AGA CCG UAG UGA
AUG AGA CCG UAG UGA
TAC
tRNA molecule
Anti codon
AUG AGA CCG UAG UGA
TAC
AUG AGA CCG UAG UGA
TCT
AUG AGA CCG UAG UGA
TCT
AUG AGA CCG UAG UGA
GGC
AUG AGA CCG UAG UGA
GGC
AUG AGA CCG UAG UGA
ATC
AUG AGA CCG UAG UGA
ATC
AUG AGA CCG UAG UGA
AUT
AUG AGA CCG UAG UGA
AUT
AUG AGA CCG UAG UGA
AUG AGA CCG UAG UGA
AUG AGA CCG UAG UGA
Amino acids
Peptide bond
Summary
The first step is transcription. The first step in transcription is the unwinding of the DNA molecule so that some DNA that codes for the needed protein can be transcribed. After the DNA molecule unwinds, the enzyme, RNA polymerase lines up nucleotides to create a strand of mRNA. After transcription, the new RNA strand is released and the two unzipped DNA strands bind together again. Since after this occurs the DNA strand is back to normal this step can repeat.
Summary
The next step is Translation. In this, mRNA is sent to the cytoplasm, where it binds to the RNA. Once the mRNA is in place, tRNA molecules bind to the ribosome defined by the mRNA code. At its tail end, tRNA has a “stem” that attaches to a specific amino acid. At its head, it has three nucleotides that make up an anticodon. Translation begins with the binding of the mRNA chain to the ribosome. The tRNA molecule forms a base pair with the mRNA. A peptide bond is formed between the amino acid attached to the tRNA.