RNA to Protein

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RNA to Protein
Translation and Protein synthesis
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A eukaryotic gene and its transcript
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The roles of transcription and translation in the
flow of genetic information
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The roles of transcription and translation in the
flow of genetic information
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The roles of transcription and translation in the
flow of genetic information
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The roles of transcription and translation in the
flow of genetic information
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The roles of transcription and translation in the
flow of genetic information
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Protein synthesis occurs with three stages in the
cell

• Ribosome association and initiation of
  translation
• Elongation of the polypeptide chain
• Termination of translation

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Translation the basic concept
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The triplet code
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The dictionary of the genetic code
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Ribosome association and initiation of translation
Initiation Initiation involves the reactions
that precede formation of the peptide bond
between the first two amino acids of the protein.
It requires the ribosome to bind to the mRNA,
forming an initiation complex that contains the
first aminoacyl-tRNA. This is a relatively slow
step in protein synthesis, and usually determines
the rate at which an mRNA is translated.
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An aminoacyl-tRNA synthetase joins a specific
amino acid to a tRNA
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The structure of a functioning ribosome
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Initiation factors (IF)
IF-3 is needed for 30S subunits to bind
specifically to initiation sites in mRNA. IF-2
binds a special initiator tRNA and controls its
entry into the ribosome. IF-1 binds to 30S
subunits only as a part of the complete
initiation complex. It binds to the A site and
prevents aminoacyl-tRNA from entering. Its
location also may impede the 30S subunit from
binding to the 50S subunit
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The initiation of translation
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Elongation of the polypeptide chain
Elongation Elongation includes all the reactions
from synthesis of the first peptide bond to
addition of the last amino acid. Amino acids are
added to the chain one at a time the addition of
an amino acid is the most rapid step in protein
synthesis.
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The elongation cycle of translation
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Translation
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Termination of translation
Termination Termination encompasses the steps
that are needed to release the completed
polypeptide chain at the same time, the ribosome
dissociates from the mRNA.
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The termination of translation
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Polyribosomes
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The molecular basis of sickle-cell disease a
point mutation
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Base-pair substitution
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Base-pair insertion or deletion
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A summary of transcription and translation in a
eukaryotic cell