Translation

Translation

• Process where mRNA is converted into proteins 

• This process begins in the cytoplasm on ribosomes in the RER

Players of Translation

• Ribosomes, rRNA, tRNA, and amino acids 

rRNA

• responsible for combining the small and large subunits of the ribosome together (helps to make a functional ribosome)

Formation of functional ribosome 

• Upon receiving the signal from the nucleus, the large and small subunits combine, with the aid of rRNA to form a complex

• The ribosome has 2 sites: P site and A site 

3 steps of Translation 

Initiation

Elongation

Termination 

Initiation

• binding of the small subunit to the large subunit. This requires rRNA and energy 

  • The binding of the initiation code, AUG, to the P site of the ribosome 

  • Binding of the next three letters to the A site 

Elongation

•  the mRNA is read, and the appropriate amino acid is brought to the ribosome by the tRNA. (each tRNA has a sequence of three nucleotides called anticodon - which is complementary to the mRNA codon) 

  • convert the message into an amino acid sequence

Termination 

• This occurs when the A site of the ribosome receives a terminator codon, either UAA, UAG, or UGA. These codons are not recognized by any normal tRNAs.